For the Following Question(s): Professor Juarez Thinks the Students in Her

For the following question(s) : Professor Juarez thinks the students in her statistics class this term are more creative than most students at this university. A previous study found that students at this university had a mean score of 35 on a standard creativity test. Professor Juarez finds that her class scores an average of 40 on this scale, with an estimated population standard deviation of 7. The standard deviation of the distribution of means comes out to 1.63.
-What is the t score?

A) (40 - 35) /7 = .71
B) (40 - 35) /1.63 = 3.07
C) (40 -35) /7² = 5/49 = .10
D) (40 - 35) /1.63² = 5/2.66 = 1.88