You are testing an enhanced user interface for a mortgage approval program involving multiple user...

Comprehensive and Detailed in Depth Explanation:

Since the testing involves verifying theuser interface (UI) enhancementsand ensuring that they meet the needs of multiple user roles,Use Case Testingis the most appropriate technique.

Use Case testingallows you to validateend-to-end user scenariosand ensure the system behaves correctly for each role, focusing onuser interactions and usability.

Exploratory testing (A)might be useful for finding unexpected issues, but it lacks the structured approach needed for role-based UI validation.

Boundary Value Analysis (B)is useful for testing numeric input limits, not UI roles.

Pairwise testing (D)focuses on combinatorial testing, not role-based UI testing.

The correct answer isC (Use Case testing).