Let\textquotesingle s say that $x$ is the smaller of the two numbers. So the question is $$(x+1)+x\textless100(x+1)^{2}-x^{2}=x^{2}+2x+1-x^{2}=2x+1$$. ~$$2x+1$$ is obviously odd, so the answer could be $$\text{C}$$ or $$\text{E}$$.  $$2x+1=131$$ doesn\textquotesingle t match with $$2x+1\textless100$$, so the answer is $$79$$.  Therefore, the answer is $$\text{C}$$. 
Pick two consecutive positive integers whose sum is less than $$100$$. Square both of those integers and then find the difference of the square numbers. Which of the following could be the difference? ($2007$ AMC $8$ Problem, Question \#$19$) 
Options:
a) $$2$$ 
b) $$64$$ 
c) $$79$$ 
d) $$96$$ 
e) $$131$$ 