Which statement is true?
 All squares are rhombuses. Rhombuses have 4 right angles. Therefore, all squares have 4 right angles.
 Only some squares are rhombuses. Rhombuses have 4 sides that are the same length. Therefore, only some squares have 4 sides that are the same length.
 All squares are rhombuses. Rhombuses have 4 sides that are the same length. Therefore, all squares have 4 sides that are the same length.
 Only some squares are rhombuses. Rhombuses have 4 right angles. Therefore, only some squares have 4 right angles.