Answer:
Option C. m = 102°
Explanation:
In this question two parallel lines are given as e and f and d is the transverse.
Given angles m and 79° are the interior angles on the same side of the transverse.
According to the theorem
if two lines e and f are parallel and line d is intersecting these lines, interior angles on the same side of transverse (angle m and 78°) will be supplementary angles.
m + 78° = 180°
m = 180° - 78°
m = 102°
Therefore, Option C. m = 102° is the answer.