A baseball player is asked to swing at the pitches in sets of four. The player swings at 100 sets of 4 pitches. The probability distribution for making a particular number of hits is given below. Determine the mean for this discrete probability distribution.
x 0 1 2 3 4
P(x) 0.02 0.07 0.22 0.27 0.42
A. 2
B. 4
C. 3.5
D. 3