The correct answer is: B. bottom-up manner.
In bottom-up testing, the modules at the lowest level of the program are tested first, followed by the modules at the next level, and so on until the entire program is tested. This approach is often used when the program is large and complex, or when there is a limited amount of time or resources available for testing.
Top-down testing is the opposite of bottom-up testing. In top-down testing, the modules at the highest level of the program are tested first, followed by the modules at the next level, and so on until the entire program is tested. This approach is often used when the program is small and simple, or when there is a lot of time or resources available for testing.
Ad hoc testing is a type of testing that is not based on any specific testing methodology. Instead, ad hoc testing is done by the tester using their own judgment and experience to determine what to test. This approach is often used when there is a limited amount of time or resources available for testing, or when the program is very complex and there is no time to develop a formal testing plan.
Cross-sectional testing is a type of testing that focuses on testing the interactions between different parts of the program. This approach is often used when the program is large and complex, or when there are a lot of potential interactions between different parts of the program.
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