Cholesterol belongs to the groups of lipids called

cholestrol is part of sterols / steroids which is one of the 4 classes of lipids
cholestrol characterized with 4 fused carbon rings, like all sterols do
other sterols are sex-trait hormones like testosterone etc.

other lipid groups are fats (glycerol and fatty acids), phospholipids (phosphate head and faitty acid tails), and waxes (contain alcohol group)

Cand d are correct because the rest are just showing your mistakes and you don’t want people who are reading a summary you wrote to see all the mistakes you made.