To answer this question, let's go through each option to understand why it is correct or incorrect:
Option A) Error condition hiding another error condition - This option is correct. Fault masking refers to the situation where one error condition hides another error condition. This means that when one fault occurs, it masks or conceals the presence of another fault, making it difficult to identify and debug the system.
Option B) Creating a test case which does not reveal a fault - This option is not correct. Creating a test case that does not reveal a fault is known as fault masking prevention. It aims to ensure that test cases are designed to uncover faults rather than hide them.
Option C) Masking a Fault by Developer - This option is not correct. Fault masking is not related to masking a fault by a developer. It is a phenomenon that occurs during the execution of a system or software.
Option D) Masking a Fault by tester - This option is not correct. Fault masking is not related to masking a fault by a tester. It is a phenomenon that occurs during the execution of a system or software.
The correct answer is A) Error condition hiding another error condition. This option is correct because it accurately describes the concept of fault masking, which refers to the situation where one error condition hides another error condition.