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 junior and senior tranches of an asset-backed security:
Option A:have equivalent expected returns.
Option B:have claims on separate underlying portfolios.
Option C:may be differentially impacted by prepayments or credit losses.

Answer: C