The slope between P and R is the same as the slope between Q and S. Choose the correct justification for this fact.
a. △ PTR and △ QUS are similar, so the ratio PT/TR is equal to the ratio QU/US . The slope D) between P and R and the slope between Q and S are both equal to 4/5 .
b. △ PTR and △ QUS are similar, so the ratio PT/TR is equal to the ratio US/QU , The slope between P and R and the slope between Q and S are both equal to 4/5 .
c. △ PTR and △ QUS are congruent, so the ratio TR/PT is equal to the ratio QU/US . The slope between P and R and the slope between Q and S are both equal to 5/4 .
d. △ PTR and △ QUS are congruent, so the ratio TR/PT is equal to the ratio US/QU , The slope between P and R and the slope between Q and S are both equal to 5/4 .