Vigrous contraction of uterus muscles is stimulated by :

Options

A. ADH
B. MSH
C. GH
D. Oxytocin

Answer

To answer the question regarding which hormone stimulates vigorous contraction of the uterus muscles, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Hormones Listed**: The question provides four hormones: ADH (Antidiuretic Hormone), MSH (Melanocyte-Stimulating Hormone), Growth Hormone, and Oxytocin.

2. **Understand the Function of Each Hormone**:
- **ADH**: Primarily involved in water reabsorption in the kidneys and does not play a role in uterine contractions.
- **MSH**: Involved in the pigmentation of skin and does not affect uterine muscle contraction.
- **Growth Hormone**: Responsible for growth and metabolism but does not stimulate uterine contractions.
- **Oxytocin**: Known for its role in stimulating uterine contractions during childbirth and lactation.

3. **Focus on Uterine Contraction**: The question specifically asks about the stimulation of vigorous contraction of the uterus muscles, which is crucial during childbirth.

4. **Select the Correct Hormone**: Based on the functions of the hormones, Oxytocin is the hormone that stimulates the contraction of the uterine muscles.

5. **Conclusion**: Therefore, the correct answer to the question is Oxytocin.

### Final Answer:
The hormone that stimulates vigorous contraction of the uterus muscles is **Oxytocin**.

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