Consider the following statements about Human respiratory system
1. Pharynx is called a ‘Sound Box’.
2. Trachea of frog is very short as it does not have separate neck.
3. Alveolus is the structural and functional unit of lung.
Select the correct answer using the code given below:1
1 and 2 only
2
2 and 3 only
3
1 and 3 only
4
All of the above