Question 4 (2 points) What is the beta of a portfolio comprised of the following securities? Stock A B Amount Invested $4,800 $5,600 $6,600 Security Beta 1.30 1.80 -0.70 OA) 0.6882 B) 0.2850 C) 1.2318 D) 1.2871 E) 0.8942