Question

the only way to circumscribe a circle around a parallelogram is to make the parallelogram a ______. a. rhombus b. trapezoid c. rectangle d. triangle

Explanation:

A quadrilateral can be circumscribed by a circle (cyclic quadrilateral) if and only if the sum of each pair of opposite angles is $180^\circ$. For a parallelogram, opposite angles are equal. Letting each pair of opposite angles sum to $180^\circ$ means each angle must be $90^\circ$, which defines a rectangle. A rhombus is not cyclic unless it is a square (a special case of rectangle), trapezoids are not parallelograms, and triangles are not parallelograms.

Answer:

C. rectangle