Which of the following is a constituent part of pelvic girdle?

Options

A. Obturator foramen
B. Olecranon process
C. Sigmoid notch
D. Foramen magnum

Answer

### Step-by-Step Solution:

1. **Understanding the Pelvic Girdle**: The pelvic girdle is a structure that connects the spine to the lower limbs. It consists of several bones that form the hip region.

2. **Identifying the Components**: The pelvic girdle is primarily made up of the hip bones, which include the ilium, ischium, and pubis.

3. **Recognizing the Obturator Foramen**: The obturator foramen is an opening in the pelvic girdle formed by the ischium and pubis bones. It is a significant feature of the pelvic girdle.

4. **Evaluating Other Options**:
- **Olecranon Process**: This is a part of the ulna bone located in the forearm, not related to the pelvic girdle.
- **Sigmoid Notch**: This is also part of the ulna and is involved in the articulation of the forearm, not the pelvic girdle.
- **Foramen Magnum**: This is a large opening in the occipital bone of the skull, allowing for the passage of the spinal cord, and is not part of the pelvic girdle.

5. **Conclusion**: The only correct answer from the options provided is the **obturator foramen**, as it is a constituent part of the pelvic girdle.

### Final Answer:
The constituent part of the pelvic girdle is the **obturator foramen**.

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