Which of the following amino acids are classified as conditional?

Conditional amino acids are those that are generally considered non-essential under normal physiological conditions, but may become essential in certain situations like stress, illness, or trauma. The correct choice identifies Cysteine, Glutamine, and Taurine as conditional amino acids.

Cysteine can be synthesized from the essential amino acid methionine, but its production may be insufficient during times of stress or illness, making it conditional.

Glutamine is another amino acid that can be synthesized by the body but is often required in greater amounts during periods of stress, infection, or injury, thus categorizing it as conditional.

Taurine, while technically classified as a compound derived from cysteine and not a standard amino acid in protein synthesis, is included in this context due to its role in several physiological processes that may become significant during illness or other stress-related conditions.

This understanding of conditional amino acids is crucial for holistic nutrition as it emphasizes the body's changing needs based on various factors and the importance of diet in providing adequate nutrition under those circumstances.