To answer this question, you need to understand the concept of equivalence partitioning in software testing.
Equivalence partitioning is a black box testing technique that is appropriate for all levels of testing. It is based on the idea that input data can be divided into groups or partitions that are treated equivalently by the system being tested.
The purpose of equivalence partitioning is to reduce the number of test cases required to adequately test the system, while still ensuring that all relevant scenarios are covered. By selecting representative test cases from each partition, it is possible to achieve good test coverage without testing every possible input combination.
Option A) A black box testing technique used only by developers - This option is incorrect because equivalence partitioning is not limited to use by developers only. It is a technique that can be used by testers at all levels, including developers.
Option B) A black box testing technique than can only be used during system testing - This option is incorrect because equivalence partitioning can be used at all levels of testing, including system testing, integration testing, and unit testing.
Option C) A black box testing technique appropriate to all levels of testing - This option is correct because equivalence partitioning is applicable to all levels of testing. It helps in selecting representative test cases from each partition to achieve good test coverage.
Option D) A white box testing technique appropriate for component testing - This option is incorrect because equivalence partitioning is a black box testing technique, not a white box testing technique. It focuses on the behavior and functionality of the system being tested, rather than the internal structure or code of the system.
Therefore, the correct answer is C) A black box testing technique appropriate to all levels of testing.