Answer:
Option C is correct.
The expression represents the number of stamps Erykah has : 3r -6
Step-by-step explanation:
Let r be the number of stamps Chris has.
as per the given condition: Erykah has 6 less than 3 times the number of stamps in her collection that Chris has in his.
"3 times the number of stamps Chris has" means 3r
"6 less than 3 times number of stamps Chris has" which means subtract 6 from 3r i,e 3r -6
therefore, the expression 3r -6 represents the number of stamps Erykah has.