Solution

The correct answer is option 3.

Key Points

• The execution time of a programme is the time that a processor spends actually executing the program's instructions.
• The second kind of time is calendar time It is the familiar time that we normally experience.
• Clock time is the normal wall clock time.

and Software reliability is described with respect to all these.

∴ Hence the correct answer is (A), (B) and (C).

Additional Information

Software reliability, like hardware reliability, is defined as the probability that the software system will work without failure under specified conditions and for a specified period of time.