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 yield spread of a specific bond over the standard swap rate in that currency of the same tenor is best described as the:
Option A:I-spread.
Option B:Z-spread.
Option C:G-spread.

Answer: A