All Teachers would be required to undergo at least One in-service Training course during every Five Years. It was proposed in_________________?

A. National Education Policy 1978
B. First Educational Conference 1947
C. Education Commission 1959
D. All of these included

The correct answer to the question: "All Teachers would be required to undergo at least One in-service Training course during every Five Years. It was proposed in_________________?" is "National Education Policy 1978".