28.
A:
Rice bran oil because it contains C 18:2 ∆9c, 12c
B:
Flax seed oil because it contains C 18:3 ∆9c, 12c, 15c
C:
Olive oil because it contains C 18:1 ∆9c
D:
Black- currant seed oil because it contains C 18:3 ∆ 6c, 9c, 12c
The answer is: B