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 process of moving credit ratings of different issues up or down from the issuer rating in response to different payment priorities is best described as:
Option A:notching.
Option B:structural subordination.
Option C:cross-default provisions.

Answer: A