Refer to Table 21 The Marginal Cost of the Third Unit of Output in |

Multiple Choice

Refer to Table 21.5: Table 21.5
$\begin{array} { | c | c | c | c | c | c | } \hline \mathrm { Q } & \mathrm { TFC } & \mathrm { TVC } & \mathrm { TC } & \text { AVC } & \text { MC } \\\hline 0 & & & 15 & - & - \\\hline 1 & & & 23 & & \\\hline 2 & & & & & 4 \\\hline 3 & & 15 & & & \\\hline\end{array}$ The marginal cost of the third unit of output in Table 21.5 is

A) $4.
B) $3.
C) $30.
D) $15.