C is the answer. Congruent is just a synonym of similar therefore C is the answer.
Answer:
Step-by-step explanation:
Given that the number of males in the classroom is three more than twice the number of females.
the total number of students is 57
Let x be the no of males then no of females = 
Also we have 3 more than twice no of females as

This equals x

No of males = 39, no of females = 18