CodeLab is

(A) an IDE (integrated development environment)

(B) an AI-based intelligent tutoring system

(C) an online set of interactive exercises with immediate feedback

(D) software testing system

Answer:C) an online set of interactive exercises with immediate feedback

Explanation: CodeLab is defined as the program that is online based an provides the services like giving knowledge about computer programming, learning etc. It has the ability to be accessed from anywhere in the world and provides the results just after activities are done on it.

Other options are incorrect because these are online services but not related with knowledge of computer program. Thus, the correct option is option (C).