The failure of thyroid secretion from infancy leading to dwarfism and mental retardation is included under

Options

A. Grave's disease
B. Cretinism
C. Simple goitre
D. Myxoedema

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about a condition resulting from the failure of thyroid secretion from infancy, leading to dwarfism and mental retardation.

2. **Identifying Key Terms**: The key terms in the question are "thyroid secretion," "infancy," "dwarfism," and "mental retardation."

3. **Recognizing Thyroid Disorders**: The thyroid gland produces hormones like thyroxin, which are crucial for growth and metabolism. A deficiency in these hormones can lead to various disorders.

4. **Exploring Conditions Related to Thyroid Failure**:
- **Cretinism**: This condition is specifically associated with hypothyroidism in infants, leading to growth retardation (dwarfism) and mental impairment.
- **Mixed Edema**: This condition occurs in adults due to hypothyroidism, not in infants.
- **Grave Disease**: This is related to hyperthyroidism, characterized by excessive thyroid hormone production, not a deficiency.
- **Simple Goiter**: This condition is caused by iodine deficiency but does not specifically lead to dwarfism and mental retardation.

5. **Conclusion**: Based on the information, the condition that fits the description of thyroid failure from infancy leading to dwarfism and mental retardation is **cretinism**.

**Final Answer**: Cretinism

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