Your portfolio is comprised of 40 percent of stock X, 15 percent of stock Y, and 45 percent of stock Z. Stock X has a beta of 1.16, stock Y has a beta of 1.47, and stock Z has a beta of 0.42. What is the beta of your portfolio?
A. 0.87
B. 1.09
C. 1.13
D. 1.18
E. 1.21