In human nutrition, some amino acids cannot be synthesized by the body and must be obtained from the diet. Which of the following is an essential amino acid in humans?

The reaction X-C-C-Y → X-Y + C=C depicts the activity of a particular class of enzymes. Identify the enzyme class 'E' from the following options:

Match List I with List II: List I A. Trypsin B. Morphine C. Concanavalin A D. Collagen List II I. Intercellular ground substance II. Lectin III. Enzyme IV. Alkaloid Choose the correct answer from the options given below: