The true statement about the Proof of the Pythagorean Theorem is:
To make a right triangle in the center, the area of the smaller two squares must add to equal the area of the largest square.
This correctly reflects the Pythagorean Theorem, which states that in a right triangle, the sum of the squares of the lengths of the two legs (the smaller two squares) is equal to the square of the length of the hypotenuse (the largest square). Therefore, \( a^2 + b^2 = c^2 \), where \( c \) is the length of the hypotenuse, and \( a \) and \( b \) are the lengths of the other two sides.