Directions (66-70) : Read this sentence to find out whether there is any grammatical mistake/error in it. The error, if any, will be in one part of the sentence. Mark the part with the error as your answer.

If there is no error, mark 'No error' as your answer. Ignore the errors of punctuation, if any.
Pummy immediately realised / that her mother was trying / to explain the important of / giving proper instructions.

A) Puniiny immediately realised

B) that her mother was trying

C) to explain the important of

D) giving proper instructions.

E) No error

Correct answer:
C) to explain the important of



Please provide the error details in above question