Detailed Explanation:

Rationale for Correct Answer: Setting version = " 3.1.4 " pins the module to that exact version, preventing Terraform from selecting any newer version. This is the strongest guard against unexpected changes (including potential breaking changes) because it does not allow upgrades unless you explicitly change the version constraint.

Analysis of Incorrect Options (Distractors):

A: Incorrect. This allows any version < 3.2 (including 3.1.5, 3.1.9, etc.). Those may still introduce behavioral changes you want to avoid.

B: Incorrect. This forces Terraform to use 3.1.5 or newer, the opposite of what you want.

D: Incorrect. ~ > 3.1.4 allows patch-level updates (e.g., 3.1.5, 3.1.9) and could still introduce changes your team wants to avoid.

Key Concept: Module version constraints and pinning to avoid unexpected upgrades.