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.

Assuming no change in the credit risk of a bond, the presence of an embedded put option:
Option A:reduces the effective duration of the bond.
Option B:increases the effective duration of the bond.
Option C:does not change the effective duration of the bond.

Answer: A