Question

Select the odd one out. Give reason for your choice:

• A. Thoracic cavity
• B. Abdominal cavity
• C. Diaphragm
• D. Rib cage

Answer 1

The correct option is B

Abdominal cavity

The correct option is B:

Explanation of the correct option:

1. The abdominal cavity lies below the thoracic cavity.
2. It is not part of the respiratory system.
   

Explanation for incorrect options

Option A:

1. The thoracic cavity is separated from the abdominal cavity by the presence of a diaphragm.
2. It is also known as the chest cavity and is enclosed by the sternum, ribs and spine.

Option C:

1. The diaphragm is the muscular partition that separates the thoracic and abdominal cavity.

Option D:

1. The rib cage is present in the thoracic cavity and is involved in the protection of organs.
2. It helps in the process of breathing as during inspiration, the ribs get elevated and during exhalation the ribs get depressed.

Final answer: Abdominal cavity is the odd one out.