How Do Unsaturated Fatty Acids Help Keep Any Membrane More

How do unsaturated fatty acids help keep any membrane more fluid at lower temperatures?

A) The double bonds form kinks in the fatty acid tails that prevent adjacent lipids from packing tightly together.
B) Unsaturated fatty acids have a higher cholesterol content that prevents adjacent lipids from packing tightly together.
C) Unsaturated fatty acids are more polar than saturated fatty acids.
D) The double bonds result in shorter fatty acid tails and therefore thinner membranes.