**Core Concept**
Essential amino acids are a group of amino acids that the human body cannot synthesize on its own and must be obtained through the diet. These amino acids are crucial for various bodily functions, including protein synthesis, enzyme production, and hormone regulation.

**Why the Correct Answer is Right**
The correct answer includes non-essential amino acids, which can be synthesized by the human body. The body's ability to synthesize these amino acids eliminates the need for dietary intake. The human body synthesizes non-essential amino acids through various metabolic pathways, including transamination, deamination, and transulfuration reactions.

**Why Each Wrong Option is Incorrect**
**Option A:** - This is an essential amino acid that cannot be synthesized by the human body and must be obtained through the diet.
**Option B:** - This is also an essential amino acid required by the human body for various bodily functions.
**Option C:** - This option is incorrect because it is a non-essential amino acid that can be synthesized by the human body.

**Clinical Pearl / High-Yield Fact**
Remember that essential amino acids are not produced by the human body and must be obtained through the diet. The recommended daily intake of essential amino acids varies based on factors such as age, sex, and overall health status.

**Correct Answer:** C.