The answer is letter B. legs

This Is a Certified Answer

Certified answers contain reliable, trustworthy information vouched for by a hand-picked team of experts. Brainly has millions of high quality answers, all of them carefully moderated by our most trusted community members, but certified answers are the finest of the finest.
The congruent segments in an isosceles trapezoid is called b. legs 

On the figure below, the:
bases are line segment AB and line segment CD.
legs are line segment BD and line segment AC.
vertices are points A, B, C, and D.
sides are line segments AB, CD, BD, AC.
7 cm not 7 mc, by the way. ._. Hope it help. ☺