Read the following statement about human respiration.
(i) trachea divides at the level of 6th thoracic vertebra
(ii) terminal bronchioles alveoli and their ducts form the respiratory part of this system
(iii) contraction of diaphragm increases volume of thoracic chamber dorsoventrally
(iv) the internal intercostals help in inspiration

Options

A. all except (iv) are true
B. only (iii) and (iv) are false
C. only (i) is true
D. none is true

Answer

D