Pellagra and Beriberi are diseases caused by vitamin deficiencies. Specifically:
- Pellagra is caused by a deficiency of niacin (vitamin B3), and symptoms include dermatitis, diarrhea, and dementia.
- Beriberi is caused by a deficiency of thiamine (vitamin B1), leading to symptoms like weakness, pain in the limbs, and heart problems.
These two diseases are directly related to the lack of essential vitamins in the diet, making option (2) the correct answer.
- Option (1), Hyperthyroidism and hypothyroidism, are disorders of the thyroid gland and are not related to vitamin deficiencies. They are typically caused by hormonal imbalances.
- Option (3), Phenylketonuria and alkaptonuria, are genetic disorders related to amino acid metabolism, not vitamin deficiencies.
- Option (4), Myositis and Myasthenia gravis, are autoimmune or muscle-related disorders and do not stem from vitamin deficiencies.
Thus, the correct answer is option (2): Pellagra and Beriberi.