To Say That You Can't Have Too Much of a Good

To say that you can't have too much of a good thing means that,for any good that you enjoy (e.g. ,pizza) :

A) higher consumption will always lead to higher utility.
B) higher consumption will cause utility to decrease at an increasing rate.
C) higher consumption will increase utility,but only up to a point;after that,utility will start to decrease.
D) it is valid to measure utility in utils.