Consider the following statements in respect of the expression Sn = n(n + 1)/2where n is an integerI. There are exactly two values of n for which Sn = 861II. Sn = S-(n + 1) and hence for any integer m, we have two values of n for which Sn = mWhich of the above are not perfect squares?

• A. 1 only
• B. 2 only
• C. Both 1 and 2
• D. Neither 1 nor 2