Which of these statements is a valid perfect square trinomial?

Statement 1: x2 + 4x + 4 = (x + 2)2
Statement 2: a2 + 2ab + ab = (a + b)2

a
Statement 1 and statement 2 are valid.

b
Statement 1 and statement 2 are invalid.

c
Only statement 1 is valid.

d
Only statement 2 is valid.