Find out whether there is any grammatical error in below sentence.The single biggest gainer in this process / was ITC's Gold Flake Kings sales are estimated / to have moved up from 50 million to 200 million sticks per month during 1987 and last year.

to have moved up from 50 million to 200 million sticks per month during 1987 and last year

The single biggest gainer in this process

was ITC's Gold Flake Kings sales are estimated

Find out whether there is any grammatical error in below sentence.The

1.	Find out whether there is any grammatical error in below sentence.The single biggest gainer in this process / was ITC's Gold Flake Kings sales are estimated / to have moved up from 50 million to 200 million sticks per month during 1987 and last year.
A.	The single biggest gainer in this process
B.	was ITC's Gold Flake Kings sales are estimated
C.	to have moved up from 50 million to 200 million sticks per month during 1987 and last year
D.	No error
Answer» C. to have moved up from 50 million to 200 million sticks per month during 1987 and last year