Which of the given statements is correct? Justify your answer/s with examples.
A ) A square and a parallelogram are quadrilaterals.
B ) Opposite sides of a square and a parallelogram are parallel.
C ) A trapezoid has one pair of parallel sides.
D ) All the above
A is correct as both the square and the parallelogram are four-sided figures. B is correct as the opposite sides of a square and parallelogram will never meet if it is stretched to be longer. C is correct as only one pair of lines of a trapezoid will not meet if it is stretched, so it has only one pair of parallel sides. Therefore, the answer D, all of the above, is correct.