ISTQB Foundation Level CTFL-Foundation Question # 17 Topic 3 Discussion

For a system with complex business rules and many branches, decision testing (a white-box technique) is appropriate because it ensures that each decision point (branch) in the code is tested. Equivalence partitioning (a black-box technique) complements this by ensuring that all functional areas (based ondifferent inputs) are adequately tested. This combination provides thorough coverage of both the internal logic and the functional requirements of the system​​.