What security measures can be employed at the Application layer?

The correct choice pertains to security measures that are specifically effective at the Application layer. Application layer security focuses on protecting the software and the application data, which includes ensuring that the applications are functioning securely and resist threats and vulnerabilities.

Firewalls, though typically associated with network security, can also be configured as web application firewalls that specifically protect web applications by filtering and monitoring HTTP traffic. Load balancers enhance application performance and availability by distributing workloads across multiple servers, but they can also include security features such as SSL termination, which secures data in transit to and from the application. Thus, they play a role in safeguarding application traffic.

This choice incorporates elements that are integral in managing application requests securely and ensuring that malicious traffic is identified and blocked, thus maintaining the integrity and confidentiality of the application.

In contrast, measures related to secure access and data encryption could fall under broader security constructs, and while they are vital, they do not encompass the application-layer focus as well as firewalls and load balancers do, which are directly influential in managing application traffic securely.