Select the option that contains a grammatical error in the underlined portion.
I have dialled the number so many times I know it at heart.
1
I have dialled the number so many times I know it at heart.
2
I have dialled the number so many times I know it at heart.
3
I have dialled the number so many times I know it at heart.
4
I have dialled the number so many times I know it at heart.