Correct Answer: (D) (a)-(iii), (b)-(i), (c)-(iv), (d)-(ii)

Step 1 - Match Protein:

Protein is the body-building nutrient. Its main job is the growth and repair of body cells and tissues. So (a) goes with (iii).

Step 2 - Match Carbohydrates:

Carbohydrates are the body's first and main source of energy, giving about 4 calories per gram. So (b) goes with (i).

Step 3 - Match Fats:

Fats act as a concentrated store of energy and also carry the fat-soluble vitamins A, D, E and K through the body. So (c) goes with (iv).

Step 4 - Match Roughage:

Roughage or dietary fibre is not digested by the body, so it gives almost no energy. Its role is to add bulk to food and prevent constipation. So (d) goes with (ii).

Hence, option (D) is correct.