An advantage in using a bottom-up vs. a top-down approach to software testing is that:

A.
interface errors are detected earlier.

B.
confidence in the system is achieved earlier.

C.
errors in critical modules are detected earlier.

D.
major functions and processing are tested earlier.

Explanation:
The bottom-up approach to software testing begins with the testing of atomic units, such as programs and modules, and works upward until a complete system testing has taken place. The advantages of using a bottom-up approach to software testing are the fact that there is no need for stubs or drivers and errors in critical modules are found earlier. The other choices in this question all refer to advantages of a top-down approach, which follows the opposite path, either in depth- first or breadth-first search order.