CAPM Practice: Validate requirements through product delivery

Delta testing (or change testing) focuses validation effort on changed requirements, complemented by regression testing for unchanged areas. It ensures that new or modified requirements are validated without requiring complete re-testing of previously validated functionality.

**Why not B:** "Testing changes before approval" describes a general change control or verification activity, not delta testing specifically. Delta testing is a type of acceptance testing performed by end users after beta testing, focusing on verifying that defects found during beta testing have been corrected. It is not simply testing changes prior to approval.

**Why not C:** "Testing the difference in budget" conflates "delta" (meaning difference) with a financial context. While delta can mean difference in mathematics, delta testing in software and business analysis refers to a specific testing phase, not a budget variance analysis.

**Why not D:** "Delta airline testing" is a nonsensical distractor with no relevance to business analysis or software testing. Delta testing is a recognized phase in the testing lifecycle that follows beta testing, where users verify that previously identified issues have been resolved before final release.