Universal Containers (UC) started to use the GitHub workflow.

The correct selection is B. A conflict becomes visible when GitHub evaluates the ServiceCase pull request against the now-updated UCDev target branch. Local add, commit, and push operations do not attempt that merge and therefore do not inherently reveal the target-branch conflict. From a build perspective, the implementation should be source-driven, reviewable, automatable, and modular. Engineering controls such as version control, package boundaries, static analysis, coding standards, and isolated development environments reduce defects early and make changes easier to understand, test, and promote. The rejected choices either rely on manual review alone, use the wrong development abstraction, or introduce custom complexity where Salesforce already provides a source-driven engineering mechanism. For this scenario, the decisive point is therefore the platform behavior represented by the selected option (B. The conflict would show in GitHub when a pull request is created from ServiceCase to UCDev.). Applying that rule consistently keeps the implementation aligned with Salesforce-supported lifecycle practices and makes the resulting change easier to review, validate, and operate across environments.

Study Guide reference: Building — Salesforce DX; package development; coding standards; static analysis; source control; secure development.