To determine which Boolean expression is equivalent to ¬(A ∧ B), we can use De Morgan's laws. De Morgan's laws state:

1. ¬(A ∧ B) = ¬A ∨ ¬B
2. ¬(A ∨ B) = ¬A ∧ ¬B

Applying the first law to ¬(A ∧ B):

¬(A ∧ B) = ¬A ∨ ¬B

Thus, the Boolean expression equivalent to ¬(A ∧ B) is A′ ∨ B′.

So the correct answer is: A′ ∨ B′

Would you like any further details or have any questions?

Here are some additional questions you might want to ask:

1. How do De Morgan's laws work?
2. Can you provide an example using De Morgan's laws?
3. What are some applications of De Morgan's laws in digital circuits?
4. How can I simplify a Boolean expression using Boolean algebra rules?
5. What is the difference between a conjunction and a disjunction in Boolean algebra?

Tip: When working with Boolean expressions, always remember to apply De Morgan's laws to simplify expressions involving negations.