1) B and D are consecutive integers.
B + D = F, so possible chioces are:
1+2=3
2+3=5
3+4=7
4+5=9
5+6=1
6+7=3
7+8=5
8+9=7
1) on its own is insufficient. 9 is not prime.
2) C = 8.
If C = 8, then A must equal 1. Otherwise, E will be greater than 9.
So C = 8 implies A = 1 and E = 9.
Still, this doesn't give enough information about F.
B and D could be 2 and 4, in which case F is 6 and not prime, or B and D could be 1 and 2, in which case F is 3, prime.
1) B and D are consecutive integers
and 2) C = 8.
Looking at the possible choices from 1) given the constraint of 2), we can eliminate anything that has 1, 8, or 9. So the remaining possible choicse for B + D = F are:
2+3=5
3+4=7
6+7=3
Note, it can't actually be 6+7, because then there will be a carry over. But either way, 5 and 7 ae both prime.
Thus, answer is C - both statements are sufficient to answer the question.
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