Which sentence best describes the difference between a rhombus and a square?

A.
A rhombus has 4 congruent sides, but a square does not always have 4 congruent sides.

B.
A square has 4 congruent sides, but a rhombus does not always have 4 congruent sides.

C.
A rhombus has 4 right angles, but a square does not always have 4 right angles.

D.
A square has 4 right angles, but a rhombus does not always have 4 right angles.