The set of intergers can be classified into k classes, according to the remainder obtained when they are divided by K (where is a fixed natural number). The classification enables is solving even some more difficult problems of number theory e.g.
(i) even, odd classification is based on whether ramainder is 0 or 1 when divided by 2.
(ii) when divided by 3, the ramainder may be 0,1,2. Thus, there are three classes.
`n^(2)+n+1` is never divisible by

Options

A. 0,1
B. 1,2
C. 0,2
D. 0,1,2

Answer

A