Rafael is studying to become a biologist. During the week, he spends 1/3 of his time studying biology at school and 1/5 of his time studying biology at home. Between school and home, what fractional part of his time is spent studying biology. Express your answer in simplified rational form. Press enter to interact with the item, and press tab button or down arrow until reaching the Submit button once the item is selected
A3/15
B7/11
C5/12
D8/15