Given a text T, and several options, according to the question posed in the text T to choose the most appropriate option from the options as the answer, please directly output the most appropriate option, do not need to output the explanation.

The internal rate of return (IRR) is best described as the:
Option A:opportunity cost of capital.
Option B:time-weighted rate of return.
Option C:discount rate that makes the net present value equal to zero.

Answer: C