Correct option is D
A. Carotenoid cleavage dioxygenase: This enzyme is involved in the biosynthesis of strigolactone (II). Strigolactones are derived from carotenoids via cleavage by CCD (carotenoid cleavage dioxygenase).
B. ER localized cytochrome P450 monooxygenase: This enzyme is involved in the biosynthesis of brassinosteroid (I). Brassinosteroids are synthesized via multiple steps involving cytochrome P450 monooxygenases (e.g., CYP85A1, CYP90B1) that are localized in the endoplasmic reticulum.
C. ACC oxidase: This enzyme is involved in the biosynthesis of ethylene (IV). Ethylene is produced from ACC (1-aminocyclopropane-1-carboxylic acid) by ACC oxidase.
D. 9-cis-epoxycarotenoid dioxygenase: This enzyme is involved in the biosynthesis of abscisic acid (III). ABA is synthesized from carotenoids via cleavage by NCED (9-cis-epoxycarotenoid dioxygenase).
Correct Answer: (D) A-II, B-I, C-IV, D-III
