To solve this question, the user needs to be familiar with software testing and the different types of testing that are performed in software development.

The question is asking for the name of the type of testing that is also known as Link Testing. Link Testing is a type of testing that is used to verify the proper integration of different software components.

Now, let's go through each option and explain why it is right or wrong:

A. Component Integration testing: This option is correct. Component Integration testing is another name for Link Testing. This type of testing is used to verify the proper integration of different software components.

B. Component System Testing: This option is incorrect. Component System Testing is a type of testing that focuses on testing individual components of the system.

C. Component Sub System Testing: This option is incorrect. Component Sub System Testing is not a commonly used term in software testing.

D. Maintenance testing: This option is incorrect. Maintenance testing is a type of testing that is performed to verify that changes made to the software have not introduced new defects.

Therefore, the answer is: A. Component Integration testing.