1+2+2^2+2^3+2^4+2^5+2^6+2^7=？
Choose the correct choice from the following options
A) (2^4-1)(2^4+1)	B) 2^6+1	C) 2^5-1	D) 2^5+1	E) 2^5-2
From 1+2+2^2+2^3+2^4+2^5+2^6+2^7=1(2^8-1)/(2-1)=2^8-1=(2^4-1)(2^4+1), the correct answer is (2^4-1)(2^4+1).
<result>A</result>
1+2+2^2+2^3+2^4+2^5+2^6+2^7=？