The following sentence has been divided into parts. One of them may contain an error.
Select the part that contains the error from the given options. If you don’t find any error, mark ‘No error’ as your answer.
Everyone was surprised / at his indefatigable courage and determination / to achieve what he desired.

A

Everyone was surprised

B

To achieve what he desired

C

No error

D

At his indefatigable courage and determination