**Question:** Amino acid lesser in rice is

A. Lysine
B. Methionine
C. Threonine
D. Isoleucine

**Correct Answer:** A. Lysine

**Core Concept:** Rice is a staple food in many parts of the world and is a rich source of carbohydrates, but it is generally considered deficient in certain essential amino acids, which are crucial for human health and proper bodily functions. Amino acids are the building blocks of proteins and are obtained from the diet. In this question, we are discussing which amino acid is less abundant in rice.

**Why the Correct Answer is Right:** Lysine is an essential amino acid, meaning that the human body cannot synthesize it internally and it must be obtained from the diet. While rice does contain lysine, its availability is generally lower than that of other amino acids present in rice, such as arginine, threonine, and histidine. This makes lysine the correct answer because of its lower concentration in rice compared to the other options.

**Why Each Wrong Option is Incorrect:**

B. Methionine: Rice has a sufficient amount of methionine, making this option incorrect.
C. Threonine: Threonine is not significantly lower in rice, making this option incorrect.
D. Isoleucine: Isoleucine is not particularly deficient in rice, making this option incorrect.

**Clinical Pearl:** Adequate lysine intake is essential for optimal growth and development in children, as well as protein synthesis in adults. Consuming a diverse diet that includes foods rich in lysine, alongside those rich in the amino acids that rice is richer in (e.g., legumes, nuts, and seeds), can help ensure a balanced intake of essential amino acids.