Question: Which of the following is a valid application of De Morgan\'s Theorem?

Options:

1. NOT (A AND B) = NOT A OR NOT B
2. NOT (A OR B) = NOT A AND NOT B
3. A AND B = NOT (NOT A OR NOT B)
4. A OR B = NOT (NOT A AND NOT B)

Correct Answer: NOT (A AND B) = NOT A OR NOT B

Solution:

De Morgan\'s Theorem states that NOT (A AND B) = NOT A OR NOT B.