we analize each statement
1.
Trapezoid van be a square but a rectangle NO, because the sides of it do not have the same measure
2.
Rhombus can be a square but rectangle NO
3.
the complementary angles add to each other 90 degrees, on a square each angle measure 90°, then the sum is greater than 90
4.
the angles formed by the diagonals add up to 90 ° since each angle will be 45 °, since the square is regular
Then right option is 4