Explanation
Tailgating is when someone follows an authorized person into a restricted area without having the proper credentials. This is usually done by pretending to be with the authorized person, or by offering assistance.
Tailgating is a social engineering attack and does not require any technical skill.

One possible reason why users are unable to reach the site after the security team updated the web server to require https:// in the URL is that the firewall rules are blocking the traffic to port 443. Port 443 is the default port for HTTPS, which is the protocol that encrypts and secures the web communication. If the firewall rules do not allow inbound traffic to port 443, then users will not be able to access the web server using HTTPS12.
To troubleshoot this issue, the security team should configure inbound firewall rules to allow traffic to port
443. This can be done by using the firewall-cmd command on RHEL 8.2, which is a tool that manages firewalld, the default firewall service on RHEL. The command to add a rule to allow traffic to port 443 is:
firewall-cmd --permanent --add-port=443/tcp
The --permanent option makes the rule persistent across reboots, and the --add-port option specifies the port number and protocol (TCP) to allow. After adding the rule, the security team should reload the firewalld service to apply the changes:
firewall-cmd --reload
The security team can verify that the rule is active by using this command:
firewall-cmd --list-ports
The output should show 443/tcp among the ports that are allowed34.
The other options are not relevant to troubleshooting this issue. Configuring the switch port with the correct VLAN may help with network segmentation or isolation, but it will not affect the HTTPS protocol or port.
Configuring the router to include the subnet of the server may help with network routing or connectivity, but it will not enable HTTPS communication. Configuring the server with a default route may help with network access or reachability, but it will not allow HTTPS traffic.

Explanation
The alert that the network engineer should configure based on the operation specifications is SNMP traps to report when the chassis temperature exceeds 95°F (35°C). SNMP (Simple Network Management Protocol) is a protocol that allows network devices to communicate their status and performance information to a central management system, called an SNMP manager. SNMP traps are messages that are sent by network devices to notify the SNMP manager of an event or condition that requires attention, such as an error, a failure, or a threshold violation. In this case, the network engineer should configure SNMP traps on the network devices to send an alert when their chassis temperature exceeds 95°F (35°C), which is the maximum operating temperature specified in the table. This alert would help the network engineer monitor and troubleshoot any overheating issues that could affect the network performance or availability. References: CompTIA Network+ N10-008 Certification Study Guide, page 228; The Official CompTIA Network+ Student Guide (Exam N10-008), page 8-11.

A brute-force attack is a type of attack that tries to guess the user's password by systematically trying all possible combinations of characters until the correct one is found12.
A brute-force attack can be performed by an attacker who has physical access to the user's computer or by a remote attacker who can intercept the user's network traffic or access the user's online account12.
A brute-force attack can prevent the user from logging in after locking the computer, as the attacker may have changed the password or locked the account after guessing the password12.
Therefore, option A is the correct answer, as a brute-force attack is the most likely attack against the user in this scenario.
The other options are incorrect, as they are not likely to cause the user's login problem.
Option B is incorrect because an on-path attack (also known as a man-in-the-middle attack) is a type of attack that intercepts and modifies the user's network traffic without the user's knowledge12. An on-path attack can compromise the user's data or credentials, but it does not prevent the user from logging in after locking the computer, unless the attacker also performs a brute-force attack12.
Option C is incorrect because a deauthentication attack is a type of attack that disconnects the user from a wireless network by sending spoofed deauthentication frames to the user's device or the access point12. A deauthentication attack can disrupt the user's network connectivity, but it does not prevent the user from logging in after locking the computer, unless the user needs to authenticate to the wireless network again12.
Option D is incorrect because a phishing attack is a type of attack that tricks the user into revealing sensitive information or clicking malicious links by sending fraudulent emails or messages that appear to be from legitimate sources12. A phishing attack can compromise the user's data or credentials, but it does not prevent the user from logging in after locking the computer, unless the user falls for the phishing attempt and changes the password or clicks a malicious link that performs a brute-force attack12.
Reference:
1: CompTIA Network+ N10-008 Study Guide, Chapter 6, Section 6.1, "Common Network Attacks", page 308-310.
2: Professor Messer's CompTIA N10-008 Network+ Course Notes, Section 6.1, "Common Network Attacks", page 46-47.

The transceivers labeled 8Gbps are likely to be used with the Fibre Channel protocol. Fibre Channel is a high-speed networking technology that is primarily used to connect storage devices to servers in storage area networks (SANs). It is capable of transmitting data at speeds of up to 8 Gbps (gigabits per second), and uses specialized transceivers to transmit and receive data over fiber optic cables.
Coaxial over Ethernet (CoE) is a networking technology that uses coaxial cables to transmit data, and is not related to the transceivers in question. Internet Small Computer Systems Interface (iSCSI) is a protocol that allows devices to communicate over a network using the SCSI protocol, and does not typically use specialized transceivers. Gigabit interface converter (GBIC) is a type of transceiver used to transmit and receive data over fiber optic cables, but it is not capable of transmitting data at 8 Gbps.