Assertion (A): log₂ 16 = 4.

Reason (R): log_a (bc) = log_a b + log_a c

1. Assertion (A) is true, Reason (R) is false.

2. Assertion (A) is false, Reason (R) is true.

3. Both Assertion (A) and Reason (R) are true, and Reason (R) is the correct reason for Assertion (A).

4. Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct reason (or explanation) for Assertion (A).

log_a (bc) = log_a b + log_a c

This is a fundamental property of logarithms, known as the product rule. It states that the logarithm of a product is the sum of the logarithms of the individual factors.

∴ Reason (R) is true.

Given, log₂ 16

⇒ log₂ (4 x 4)

⇒ log₂ 4 + log₂ 4

⇒ log₂ 2² + log₂ 2²

⇒ 2log₂ 2 + 2log₂ 2

⇒ 2 + 2

⇒ 4.

∴ Assertion (A) is true.

∴ Both Assertion (A) and Reason (R) are true, and Reason (R) is the correct reason (or explanation) for Assertion (A).

Hence, option 3 is the correct option.