Explanation
TACACS+ (Terminal Access Controller Access Control System Plus) can be used to centrally manage credentials for various types of administrative privileges on configured network devices. This protocol separates authentication, authorization, and accounting (AAA) functions, providing more granular control over access to network resources.
References:
Network+ N10-007 Certification Exam Objectives, Objective 4.2: Given a scenario, implement secure network administration principles.

To access production applications and data, developers must first connect remotely to a different server. From there, the developers are able to access production data. This best represents a jump box, which is a system on a network used to access and manage devices in a separate security zone. A jump box is a hardened and monitored device that spans two dissimilar security zones and provides a controlled means of access between them1 A jump box is often used to provide transparent management of devices on a DMZ or a production environment once a remote session has been established. The jump box acts as a single audit point for traffic and also a single place where user accounts can be managed. A prospective administrator or developer must log into the jump box in order to gain access to the production assets and all access can be logged for later audit1 The other options do not best represent the scenario. A management plane is a logical part of a network device that provides administrative functions such as configuration, monitoring, and troubleshooting2 A proxy server is a device that acts as an intermediary between a client and a server, providing functions such as caching, filtering, or load balancing3 An out-of-band management device is a device that provides a separate and dedicated channel for network management, such as a console port or a modem. A site-to-site VPN is a secure connection between two or more networks over the internet, using encryption and tunneling protocols.
Reference:
https://en.wikipedia.org/wiki/Jump_server

Spanning Tree Protocol (STP) should be enabled when configuring redundant network links between switches.
STP ensures that only one active path is used at a time, preventing network loops and stability issues.
References:
* CompTIA Network+ Certification Study Guide

Explanation
Input sanitization is the process of validating and filtering the user input to prevent malicious code or commands from being executed on the web server or the web browser. Input sanitization can prevent this type of attack, which is called cross-site scripting (XSS), by removing or escaping any special characters or scripts that are not expected or allowed in the input field. Input sanitization can be implemented on the server-side or the client-side, or both, to enhance the security of the web application.
References
1: Web Application Attacks - N10-008 CompTIA Network+ : 3.2
2: CompTIA Network+ N10-008 Certification Study Guide, page 317
3: CompTIA Network+ N10-008 Exam Subnetting Quiz, question 15
4: CompTIA Network+ N10-008 Certification Practice Test, question 6