Lack of fruits and vegetables can cause deficiency of what in the diet?

Correct answer: Vitamins, minerals and fibre

Fruits and vegetables are important protective foods because they commonly supply vitamins, minerals, fibre and several beneficial plant compounds. If a person regularly eats too few of them, the diet may become low in these nutrients, although the exact deficiency depends on the rest of the diet. They are not the only possible sources, but their absence can reduce dietary variety and nutritional quality. Thus, option A is the only academically correct answer.