The profits from selling T-shirts at store A are shown in the graph. The profit y for selling x T-shirts at store B is represented by the equation y= 3.75x. Which of the following statements is true?
a. Store A made a greater profit per T-shirt.
b. Store B made a greater profit per T-shirt.
c. Store A made a profit of $3.50 per T-shirt
d. Store B made a profit of $4 per T-shirt.