Carol and Jennie are both good at math. At Carol's school, students get rewarded with points toward a gift certificate from a local ice cream shop every time they show up to the math club meetings after school

At Jennie's school, students on the math team get rewarded with an ice cream gift certificate every time they win a math meet. Based on research regarding rewards, which girl is more likely to participate on the math team?
a. Carol, because being rewarded for participating helps maintain motivation.
b. Carol, because her school values participation more than winning.
c. Jennie, because she gets more rewards than Carol.
d. Jennie, because being rewarded for doing something well helps maintain motivation.

Answer: d