Comparing arachidic acid (a saturated fatty acid) and eicosapentaenoic acid (a polyunsaturated fatty acid), both containing 20 carbon atoms, why does arachidic acid have a significantly higher melting point?

Because arachidic acid has more hydrogen atoms.

Because arachidic acid has double bonds and branching.

Because eicosapentaenoic acid is polyunsaturated.

Because eicosapentaenoic acid has a shorter hydrocarbon chain.