Statement 1) if (a-7)(b-7)(c-7) = 0 and a,b,c are all integers then either of a, b or c can be 7 Not sufficient
Statement 2) bc = 18 Does not help answer the question
Let us combine both the statments. if b*c = 18 and b,c are integers this clearly implies that either of b or c cannot be a mulitple of 7. Hence it can be concluded that a = 7.
Combining both the statements helps us answer the question. Hence C