An electronics salesman earned a x% commission on each of the m digital music player he sold in the month of March at the retail price of $p. In April, he earned a y% commission on sales of the same item, and the price remained the sale. If y > x and he sold q more digital music players in April than in March, how much more money did he earn selling digital music players in April than in March?
A. \(\frac{p}{100} [ym-x(m+q)]\)
B. \(\frac{p}{100} [x(m+q)+ym]\)
C. \(p[y(m-q)-xm]\)
D. \(\frac{p}{100}[x(m+q)-ym]\)
E. \(\frac{p}{100}[y(m+q)-xm]\)