Which of the following testing is also known as white-box testing?

Question

Accepted Answer

The correct option is (3):
White-box testing is a fundamental technique where the tester has complete knowledge of the system's internal structure, logic, and source code. Because the internal workings, or the "box," are entirely visible and transparent to the tester, this methodology is universally known by the powerful metaphor **Glass box testing**. The term 'glass box' perfectly conveys the concept of seeing right through the software's outer shell into the code, enabling a thorough check of all execution paths, loops, conditional statements, and internal data flows. This method is crucial for verifying that the code is implemented correctly, efficiently, and according to the internal design specifications.

The incorrect option is (1):
Error guessing technique is a method used in *Black-Box testing*, where the tester has no knowledge of the internal code. In this technique, the tester relies heavily on intuition, past experience with similar software, and knowledge of common programming errors to create test cases. Its goal is to predict where defects are most likely to be found without reviewing the source code itself, making it fundamentally different from a white-box approach.

The incorrect option is (2):
Design based testing describes a strategy where test cases are systematically created by referring to the system’s high-level or detailed design documentation. While both white-box and black-box testing can be based on the design, this term is not a standard, interchangeable synonym for white-box testing. It is a testing *input* or *strategy* focusing on the blueprint, whereas "Glass box testing" is the well-recognized name for the *type* of testing with code visibility.

The incorrect option is (4):
This option is incorrect because Option 3, "Glass box testing," is a correct and widely accepted synonym for white-box testing. The visibility into the inner structure of the software is the defining characteristic of this testing type, and the term 'glass box' effectively captures this essential concept.