1 is to a because corresponding angles are located in the same location, comparative to each line.
2 is to d because one, they are on the same side of the transversal, and two, they are "facing" each other.
3 is to c because vertical angles are formed opposite to each other when two lines intersect, like shown.
4 is to b because they are on different sides of the transversal, and are "facing" each other.
5 is to e because they are not "facing" each other, and they are on different sides of the transversal.