Ans: When 7 divides k, the remainder is 6.
When 7 divides k+2, the remainder will be 6+2 i.e. 8. Since we are dividing by 7 we cannot get a remainder more than 7 ( the remainders possible, when 7 is the divisor, are 0,1,2,3,4,5,6). Thus, we need to divide 8 by 7 to get the actual remainder and that is 1. Option 1.
Another method, would be to take some value of k such that when it is divided by 7, the remainder is 6. The smallest positive value that we can take is 13 (7+6=13). k+2= 15.
When 15 is divided by 7, the remainder is 1.