Dolores bought an ice cream with a total utility of 10 utils. Because she loves avocado flavor she bought another ice cream resulting to a total utility of 35 utils. After eating the second ice cream she bought her third ice cream increasing her total utility to 50 utils. On her forth ice cream , Dolores worried that she might get fat so she decided to eat her forth and last ice cream which gave her the same utility of 50 utils. What is the marginal utility of Dolores when she ate the second ice cream? *

A. 25 utils

B. 15 utils

C. 0 utils

D. 10 utils