Physical , psychromotor and mental development is retarded in an individual affected with

Options

A. Down's syndrome
B. Sickle cell anaemia
C. Turner's syndrome
D. Colour blindness

Answer

To solve the question regarding which condition leads to physical, psychomotor, and mental development retardation, we will analyze each option provided.

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about a condition that causes retardation in physical, psychomotor, and mental development. This indicates a genetic or chromosomal disorder that affects overall growth and cognitive abilities.

2. **Analyzing the Options**:
- **Option A: Down syndrome**: This is a genetic disorder caused by the presence of an extra copy of chromosome 21 (trisomy 21). Individuals with Down syndrome often exhibit short stature, a small round head, and significant delays in physical and mental development.
- **Option B: Sickle cell anemia**: This is primarily a blood disorder characterized by the production of abnormal hemoglobin, leading to sickle-shaped red blood cells. While it affects health, it does not typically cause developmental retardation in the same way as Down syndrome.
- **Option C: Turner syndrome**: This condition occurs due to the absence of one X chromosome in females (karyotype 45,XO). While it can lead to some developmental issues, it does not typically cause the same level of mental retardation as Down syndrome.
- **Option D: Color blindness**: This is a visual impairment that affects the ability to distinguish between certain colors. It does not affect physical or mental development.

3. **Identifying the Correct Answer**: Based on the analysis, Down syndrome is the condition that is most associated with physical, psychomotor, and mental retardation. Therefore, the correct answer is **Option A: Down syndrome**.

### Final Answer:
The condition that leads to physical, psychomotor, and mental development retardation is **Down syndrome**.

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