Respuesta :

Answer:

b

Step-by-step explanation:

(2a + ★)(2a - ★) =4a²-b²

If you substitute b for ★ in the equation. We have;

(2a + b)(2a - b) = 4a² - b²

4a² - 2ab + 2ab -b² = 4a²-b²

4a²-b²= 4a² - b².

So 'b' is correct