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.

A manufacturing company receives a ratings upgrade and the price increases on its fixed-rate bond. The price increase was most likely caused by a(n):
Option A:decrease in the bond’s credit spread.
Option B:increase in the bond’s liquidity spread.
Option C:increase of the bond’s underlying benchmark rate.

Answer: A