Follow the order of operations and evaluate the exponential expression.

First, we need to simplify the expression using the order of operations (PEMDAS).

[(1 + 2)^2 x 4] - (4 - 1)^2
= [(3)^2 x 4] - (3)^2
= (9 x 4) - 9
= 36 - 9
= 27

So, the correct answer is 27.