Unsaturated fatty acids question?

Question

Which of the following is a reasonable explanation for why unsaturated fatty acids help keep any membrane more fluid at lower temperatures?

A) The double bonds form a kink in the fatty acid tail, forcing adjacent lipids to be further apart.

B) Unsaturated fatty acids have a higher cholesterol content.

C) Unsaturated fatty acids permit more water in the interior of the membrane.

D) The double bonds block interaction among the hydrophilic head groups of the lipids.

E) The double bonds result in a shorter fatty acid tail

Answer 1

A.  Because the kinked fatty acids prevent the close packing of the non-polar regions of the fatty acids, and the ends of these tails being involved in more collisions with other fatty acids as they rotate and laterally diffuse through the membrane, "stirring" things up.

Answer 2

A