Answer :
Wikipedia defines "deductive reasoning" as "Deductive reasoning, also deductive logic, logical deduction is the process of reasoning from one or more statements (premises) to reach a logically certain conclusion."
The best example of deductive reasoning from the given options is :
C. Everyone in Mr. Kim's class got an A on the test. Casey is in Mr. Kim's class, so he must have received an A on the test.
In the above sentence the logical conclusion is that "Casey must have received an A on the test." The logical conclusion is based on the two statements, "Everyone in Mr. Kim's class got an A on the test." and "Casey is in Mr. Kim's class."