Answer:
Can / Adjustable
Explanation:
Carotenoids are chemicals compounds or pigments that are found in vegetables/fruits that have colors red, orange, yellow such as carrots, pumpkins, tomatoes etc.
And the retinol in the question and also carotenoids are included in vitamin A which is found in these fruits and vegetables.
Consuming a large quantity of these food items can lead to an overload of carotenoids and that can have harmful effects for the body because the conversion to retinal is adjusted according to the demand of our bodies. Vitamin A gets used by the body as much as it is needed and the rest is left unused which can have really harmful effects.
I hope this answer helps.