1. **Problem Statement:** We are given a quadrilateral with side lengths 9, 18, 18, and 9, and it is described as a rectangle with four right angles. 2. **Recall the properties of quadrilaterals:** - A **parallelogram** has opposite sides equal and parallel. - A **rectangle** is a parallelogram with four right angles. - A **trapezoid** has only one pair of parallel sides. - A **square** has four equal sides and four right angles. - A **rhombus** has four equal sides but not necessarily right angles. 3. **Analyze the given quadrilateral:** - Opposite sides are equal: 9 and 9, 18 and 18. - It has four right angles. 4. **Conclusion:** Since it has four right angles and opposite sides equal but adjacent sides are not equal (9 ≠ 18), it is a **rectangle**. **Final answer:** B. rectangle