Answer:
c║d by Converse of Corresponding Angles postulate
Explanation:
Line 'a' is not shown as having any relationship to anything. It can be removed from the picture, and all answer choices involving line 'a' can be ignored.
Line 'b' crosses two lines (c and d), so can be considered their transversal. The marked angles are not all between c and d, nor are they all outside of c and d, so they are neither "interior" nor "exterior." Eliminating the obviously incorrect choices leaves only c║d and the choice of the Corresponding Angles postulate or its Converse.
The Corresponding Angles postulate tells you that corresponding angles are congruent where a transversal crosses parallel lines. Its Converse tells you the lines are parallel if the corresponding angles are congruent. Here, we're given angles and asked about the lines being parallel. Clearly, the applicable postulate is ...
c║d by Converse of Corresponding Angles Postulate