Josh Is Eating Pizza at His Favorite Italian Restaurant Table $19.1$

Josh is eating pizza at his favorite Italian restaurant. Below is his utility from this consumption:
$\begin{array}{|l|l|l|}\hline & \text { Total Utility } & \text { Marginal Utility } \\\hline \text { First slice of pizza } & 20 & 20 \\\hline \text { Second slice of pizza } & 39 & 19 \\\hline \text { Third slice of pizza } & - & 15 \\\hline \text { Fourth slice of pizza } & 59 & - \\\hline\end{array}$
Table $19.1$ Refer to Table 19.1.For Josh, diminishing marginal utility begins

A) After the first slice of pizza.
B) After the third slice of pizza.
C) After the second slice of pizza.
D) To increase after the first slice of pizza.