Which term describes a disease caused by deficiency of a vitamin?

• A. infection
• B. deficiency disease
• C. syndrome
• D. allergy

Answer: (B)

When a nutrient, such as a vitamin, is not available in enough quantity, the body cannot carry out certain essential functions, leading to illness. This broad situation is described by the term deficiency disease, which covers diseases caused by a lack of vitamins or other nutrients. It fits the question because it directly names a disease resulting from insufficient vitamin intake. In contrast, infection is caused by pathogens like bacteria or viruses; a syndrome is simply a set of symptoms that can occur with many different problems; and an allergy is an immune reaction to a harmless substance. For example, vitamin C deficiency can cause scurvy, illustrating how a deficiency leads to a specific disease.