a = (6)n , b = (8)n and c = (4)2n where (r)n =rrrr...(n digit number)
By Intution a2 + b + c is not equal to zero, since sum of positive integers will not be zero
Hence ' a2 + b + c = 0 ' can be excluded.
let us consider n = 1 and find the relation of a2 + b - c
Hence the answer (b) a2 + b - c is the correct answer