Question

congruent
complementary
supplementary
perpendicular
the opposite angles of a parallelogram are ...

Explanation:

In geometry, one of the key properties of a parallelogram is that its opposite angles are congruent. Congruent means having the same measure. Complementary angles add up to \(90^{\circ}\), supplementary angles add up to \(180^{\circ}\), and perpendicular refers to lines (or line - segments) that intersect at a \(90^{\circ}\) angle. None of these (complementary, supplementary, perpendicular) describe the relationship of opposite angles in a parallelogram.

Answer:

congruent