Official Answer Key & Detailed Solution
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Correct Answer: Option (D) — A is false but R is true
Concept & Option Breakdown
Standard Reference VerifiedAssertion (A) is false: Glycine, serine, and tyrosine are non-essential amino acids; the human body can synthesize them endogenously from metabolic precursors, so their dietary presence is not compulsory.
Reason (R) is true: Essential amino acids (such as leucine, isoleucine, valine, lysine, methionine, phenylalanine, threonine, tryptophan, and histidine) cannot be synthesized by human metabolic pathways and must be supplied via diet.
Tyrosine, glycine, and serine are classic non-essential amino acids made by the body, making compulsory dietary intake unnecessary.
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