Port mirroring is a feature that allows a network switch to copy the traffic from one or more ports to another port for monitoring purposes. Port mirroring can be used to analyze the network traffic from a specific source, destination, or protocol without affecting the normal operation of the network. Port mirroring can also help to detect and troubleshoot network problems, such as performance issues, security breaches, or policy violations.
The other options are not correct because they do not meet the requirements of the question. They are:
Turn on port security. Port security is a feature that restricts the number and type of devices that can connect to a switch port. Port security can help to prevent unauthorized access, MAC address spoofing, or MAC flooding attacks. However, port security does not allow the network security engineer to view the traffic from the user's PC to the switch.
Implement dynamic ARP inspection. Dynamic ARP inspection (DAI) is a feature that validates the ARP packets on a network and prevents ARP spoofing attacks. DAI can help to protect the network from man-in-the-middle, denial-of-service, or data interception attacks. However, DAI does not allow the network security engineer to view the traffic from the user's PC to the switch.
Configure 802.1Q. 802.1Q is a standard that defines how to create and manage virtual LANs (VLANs) on a network. VLANs can help to segment the network into logical groups based on function, security, or performance. However, 802.1Q does not allow the network security engineer to view the traffic from the user's PC to the switch.
Reference 1: Port Mirroring - an overview | ScienceDirect Topics 2: Network+ (Plus) Certification | CompTIA IT Certifications 3: Port Security - an overview | ScienceDirect Topics 4: Dynamic ARP Inspection - an overview | ScienceDirect Topics 5: 802.1Q - an overview | ScienceDirect Topics

The technician would most likely train the employee on using site-to-site VPNs between the two city locations and client-to-site software on the employee's laptop for all other remote access. A VPN (Virtual Private Network) is a technology that creates a secure and encrypted tunnel over a public network such as the Internet. It allows remote users or sites to access a private network as if they were directly connected to it. A site-to-site VPN connects two or more networks, such as branch offices or data centers, using a VPN gateway device at each site. A client-to-site VPN connects individual users, such as mobile workers or telecommuters, using a VPN client software on their devices. In this scenario, the employee needs to access the network from different locations, such as home, travel, or another city. Therefore, the technician would train the employee on how to use site-to-site VPNs to connect to the network from another city location that shares services, and how to use client-to-site software to connect to the network from home or travel locations. Reference: https://www.cisco.com/c/en/us/support/docs/security-vpn/ipsec-negotiation-ike-protocols/14106-how-vpn-works.html

A MAC spoofing attack consists of changing the MAC address of a network device (network card). A client computer can use Revers Address Resolution Protocol to request its Internet Protocol (IPv4) address and MAC address from a computer network to check its accuracy.

An Optical Time Domain Reflectometer (OTDR) is a device that tests the integrity of a fiber cable and is used for the building, certifying, maintaining, and troubleshooting fiber optic systems.
Fusion Splicing is a preferred way to join two fibers together by using heat. Whether the fiber was broken or not long enough, a fusion splicer will make your job easier. You would do this after finding where the break is.