Acetabulum is part of
(a) Pelvic girdle
(b) Pectoral girdle
(c) Forearm
(d) Upper arm

Options

A. Pelvic girdle
B. Pectoral girdle
C. Fore arm
D. Upper arm

Answer

To solve the question "Acetabulum is part of," we will analyze the options provided and determine the correct answer step by step.

### Step-by-Step Solution:

1. **Understanding the Term "Acetabulum":**
- The acetabulum is a cup-shaped cavity in the hip bone. It is crucial for the articulation of the thigh bone (femur) with the pelvis.

2. **Identifying the Location of the Acetabulum:**
- The acetabulum is located at the point of fusion of three bones: the ilium, ischium, and pubis. These bones together form the pelvic girdle.

3. **Analyzing the Options:**
- (a) Pelvic girdle: This is where the acetabulum is located, as it forms part of the hip joint.
- (b) Pectoral girdle: This is associated with the shoulder region and does not include the acetabulum.
- (c) Forearm: This consists of the radius and ulna and does not include the acetabulum.
- (d) Upper arm: This consists of the humerus and is not related to the acetabulum.

4. **Conclusion:**
- Based on the above analysis, the acetabulum is indeed part of the pelvic girdle. Therefore, the correct answer is **(a) Pelvic girdle**.

### Final Answer:
**(a) Pelvic girdle**