Assertion (A): Fatty acids should be a part of the balanced human diet. Reason (R): The cells of the human body cannot synthesize any fatty acids.

1. Assertion (A): Fatty acids, particularly essential fatty acids (like omega-3 and omega-6), are crucial components of cell membranes, precursors for signaling molecules, and sources of energy. They absolutely should be a part of a balanced human diet. So, Assertion (A) is true. 2. Reason (R): The cells of the human body can synthesize many fatty acids (non-essential fatty acids) from carbohydrates or proteins. However, humans cannot synthesize certain polyunsaturated fatty acids known as essential fatty acids (e.g., linoleic acid and alpha-linolenic acid); these must be obtained from the diet. The statement that the body cannot synthesize *any* fatty acids is false. 3. Since Assertion (A) is true and Reason (R) is false, the correct option should be (C). However, the provided answer key is 'A' (Both A and R are individually true and R is the correct explanation of A). This implies the examiner considered R to be true, perhaps focusing only on *essential* fatty acids and interpreting 'any' loosely. *If forced to follow key 'A', the analysis must wrongly state that the human body cannot synthesize any fatty acids and that this explains why they are needed in the diet.*