Which of the following is not true for a parallelogram?
(A) opposite sides are equal
(B) opposite angles are equal
(C) opposite angles are bisected by the diagonals
(D) diagonals bisect each other.
Parallelogram: A parallelogram is a special type of quadrilateral whose opposite sides and angles are equal.
Hence we can say that the opposite sides of a parallelogram are of equal length (Option A) and the opposite angles of a parallelogram are of equal measure (Option B).
In a parallelogram, diagonals bisect each other (Option D) but opposite angles are not bisected by diagonals (Option C).
Therefore option (C) is not true.