Which quadrilateral has exactly one pair of opposite sides parallel?

1. A quadrilateral is a closed shape made of four straight line segments. 2. A trapezium is a quadrilateral with one pair of opposite sides parallel. 3. A rhombus and a rectangle are both parallelograms, so each has two such pairs. 4. A pentagon has five sides, so it is not a quadrilateral at all. _Source: Siyavula Mathematics Grade 11 (Everything Maths, CC BY 4.0), Chapter 4: Analytical geometry_