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’.
When a student works on a mathematical problem, (1)/ he comes to a stage beyond which he do not (2)/ know how to proceed, and where he is in doubt and perplexity. (3)/ No error (4)

Options

A. 1
B. 2
C. 3
D. 4

Answer

B