A
2 x 8+16 = 32 16 x 4 = 64
B
2 x 4 +8 = 16 8 x 8 = 64
C
4 x 8 + 32 = 64 2 x 32 = 64
1 l l l l 8 5 l l l l 40
2 l l l l 16 6 l l l l 48
3 l l l l 24 7 l l l l 56
4 l l l l 32 8 l l l l 64
The teacher has 64 or more pencils to give out.
Hope this helps you choice your answer. :)