Stewie Enjoys Watching DVDs and Listening to His IPod

Multiple Choice

Stewie enjoys watching DVDs and listening to his iPod.Suppose his utility function is given by U(D,I) = 3D + 4(D x I) ,where D is the number of hours he spends watching DVDs and I is the number of hours he spends listening to his iPod.Which of the following combination will provide Stewie with the greatest amount of satisfaction?

A) 4 hours of watching DVDs and 8 hours of listening to his iPod
B) 6 hours of watching DVDs and 6 hours of listening to his iPod
C) 2 hours of watching DVDs and 10 hours of listening to his iPod
D) 8 hours of watching DVDs and 6 hours of listening to his iPod