Which of the following values for kkk makes GCD(k2+1,(k+1)2+1)>1\text{GCD}(k^2+1, (k+1)^2+1) > 1GCD(k2+1,(k+1)2+1)>1?
k=1k=1k=1
k=2k=2k=2
k=3k=3k=3
k=4k=4k=4