The statement: A rectangle is a square if all the 4 sides are equal, in if-then form would be

Question

(A) If all the 4 sides in a square are equal then it is a rectangle (B) If all the 4 angles in a rectangle are equal then it is a square (C) If a rectangle is a square then all its 4 sides are equal. (D) If all the 4 sides in a rectangle are equal then it is a square