The correct answer is option (d).
Work Step by Step
Lipids are a group of hydrophobic or amphiphilic molecules that occur naturally. They include fats, sterols, monoglycerides, diglycerides, triglycerides, phospholipids, waxes, fat-soluble vitamins, and others. Step 2 of 3 Triglycerides are glycerolipids with fatty acids esterified to glycerol. The three alcoholic groups are esterified with three fatty acids in a triglyceride. Hence, option (a) is not correct. Waxes are organic compounds composed of carboxylic acids esterified to long chain alcohols or substituted hydrocarbons. They do not have a ring structure. Hence, option (b) is not correct. Phospholipids are derived from glycerolipids. One of the alcohols of the glycerol is esterified to a phosphate; the remaining two alcoholic groups are esterified to fatty acids, in phospholipids. There are no ring structures in phospholipids. Hence, option (c) is not correct. Step 3 of 3 Steroids are organic compounds with four fused rings; three of them are cyclohexane rings and the other is a cyclopentane ring. They serve an important function in maintaining the structural integrity of cell membranes. Hence, the correct answer is option (d).