Most common cause of mental retardation (Congenital) in male children is

Options

A. Jacob syndrome or super males
B. Down's syndrome
C. Patauo's syndrome
D. Phenyl ketonuria

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the most common cause of congenital mental retardation in male children. This indicates that we need to identify a genetic condition that leads to mental retardation and is prevalent among males.

2. **Analyzing the Options**: The options given are:
- Jacob's syndrome (super males)
- Down syndrome
- Patel syndrome
- Phenylketonuria

3. **Evaluating Each Option**:
- **Jacob's Syndrome**: This condition is characterized by the presence of an extra Y chromosome (XYY). While it can lead to some developmental issues, it is not commonly associated with mental retardation.
- **Down Syndrome**: This is caused by an extra copy of chromosome 21 (trisomy 21). It is well-known to cause developmental delays and mental retardation. It is also more common in males.
- **Patel Syndrome**: This is a rare genetic disorder and is not commonly associated with mental retardation.
- **Phenylketonuria (PKU)**: This is a metabolic disorder that can lead to mental retardation if not treated, but it is less common compared to Down syndrome.

4. **Conclusion**: After evaluating the options, Down syndrome is identified as the most common cause of congenital mental retardation in male children due to its prevalence and the specific genetic anomaly associated with it.

5. **Final Answer**: The most common cause of congenital mental retardation in male children is **Down syndrome**.

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