To determine which of the options is a valid Boundary Value Analysis test case, we need to consider the boundaries that define different tax rates.
In this system, there are three tax rates based on different salary ranges:
- The first £4000 is tax-free.
- The next £1500 is taxed at 10%.
- The next £28000 is taxed at 22%.
- Any further amount is taxed at 40%.
Based on these tax rates, we can determine the test cases for Boundary Value Analysis:
A. £1500 - This is the boundary between the tax-free range and the 10% tax range. It is a valid test case because it tests the transition from no tax to a taxed amount.
B. £32001 - This is beyond the highest salary range with a fixed tax rate. It is a valid test case because it tests the system's behavior when the salary exceeds the highest tax range.
C. £33501 - This is beyond the highest salary range with a fixed tax rate. It is a valid test case because it tests the system's behavior when the salary exceeds the highest tax range.
D. £28000 - This is the boundary between the 22% tax range and the amount taxed at 40%. It is a valid test case because it tests the transition from a lower tax rate to a higher tax rate.
To the nearest whole pound, option C (£33501) is a valid Boundary Value Analysis test case because it tests the system's behavior when the salary exceeds the highest tax range.