To answer this question, the only important values are:
Bin
Units sold = 14,000
Variable cost = $80
Arks
Units sold = 56,000
Variable cost = $60
Calculating for total variable cost:
Total variable cost = $80 * 14,000 + $60 * 56,000
Total variable cost = $4,480,000
Calculating for e:
e = Total variable cost / Total units sold
e = $4,480,000/(14,000+56,000)
e = $64
Answer is letter A.