Answer:
a. SSS
Explanation:
These angles can be proven through SSS, which stands for side, side, side. This is used when all three sides of a triangle are proven congruent to its corresponding side on another triangle. In this case, the tick marks on the triangle prove that each side of the triangle is congruent to another on the other triangle. Remember, that if two lines have the same number of ticks then they are congruent.