Which of the following options is correct?
A trapezium has one pair of sides parallel.
A parallelogram has two pairs of parallel sides.
Rectangle is a parallelogram in which only opposite sides are equal, not all the sides are equal.
A trapezium has one pair of sides parallel whereas a parallelogram has two pairs of equal opposite sides. So, every parallelogram is a trapezium but trapezium is not a parallelogram. Also trapezium does not have equal opposite angles.