The correct answer is option 3. A-III, B-IV, C-I, D-II.
Let us go through each pair in detail:
A. RNA (Ribonucleic acid) - III. Ribose:
RNA is a nucleic acid that plays a crucial role in protein synthesis. The sugar component in RNA is ribose. Ribose is a pentose sugar (a sugar with five carbon atoms), and it is specifically found in the backbone of RNA molecules.
B. Invert sugar - IV. Sucrose:
Invert sugar is a mixture of glucose and fructose formed by the hydrolysis of sucrose. Sucrose is a disaccharide composed of one molecule of glucose and one molecule of fructose.
C. Animal starch - I. Glycogen:
Animal starch refers to glycogen, which is a polysaccharide (multiple sugar units) that serves as a storage form of glucose in animals. Glycogen is primarily found in the liver and muscles and can be broken down into glucose when energy is needed.
D. Milk sugar - II. Lactose:
Milk sugar is lactose, which is a disaccharide sugar found in milk. Lactose is composed of one molecule of glucose and one molecule of galactose.
So, the correct match is 3. A-III, B-IV, C-I, D-II. | 
