A store is setting up wireless access for employees.

A site survey is the formal process used to determine the required number, placement, and configuration of wireless access points (APs). Security+ SY0-701 states that site surveys measure RF propagation, identify dead zones, account for building materials, detect interference sources, and evaluate coverage overlap. This information allows network engineers to deploy the fewest APs necessary while still ensuring full coverage.

Although heat maps (C) are generated as a result of a site survey, they are visualization tools—not the actual survey process. A signal locator (A) is not a standardized tool in wireless planning. WPA3 (B) is a wireless security protocol and has no impact on access point planning or coverage optimization.

A full site survey ensures optimal AP placement to balance coverage, performance, and cost—exactly the concern described in the scenario.

Thus, the correct answer is D: Site survey.