Lipid Bilayers with High Concentrations of Gangliosides Are Rare

Lipid bilayers with high concentrations of gangliosides are rare.Which of the following explanations is correct?

A) The hydrophobic tails on gangliosides form a conical shape rather than a cylindrical shape making close packing difficult.
B) Gangliosides contain large headgroups making close packing difficult.
C) Gangliosides contain trans fatty acids resulting in a bent hydrophobic tail making close packing difficult.
D) All of the above are correct.
E) None of the above is correct.