In the following question, some part of the sentence may have errors. Find out which part of the sentence has an error and select the appropriate option. If a sentence is free from error, select 'No Error'.

No sooner had he finished (a)/ his morning walk (b)/ when it began to rain. (c)/ No Error (d)

A

No sooner had he finished

B

his morning walk

C

when it began to rain

D

No Error