The right answer is: vitamin C and choline
Choline (vitamin B4) is the precursor on the one hand acetylcholine (important neurotransmitter and neuromodulator) and on the other hand, the cascade initiated by betaine (intermediate in the biological methylation and precursor of membrane lipids). In this, it is considered, by extension, as an integral part of the family of B vitamins,
Vitamin C protects against cellular aging, is essential for the immune defenses and increases the assimilation of iron of plant origin. It also contributes to the formation of collagen. Its deficiency leads to a disease called scurvy (hence the ascorbic acid name of vitamin C).
It depends on your teacher, it should be A. It could be B if that’s what your teacher wants but I would go with A.