Guard cell movement furnishes an example of

An $A$ in the pulmonary volume $B$ the intra-pulmonary pressure to less than the atmospheric pressure which forces the air from $C$ to move into the lungs,i.e.,$D$. Choose the correct options for the blanks $A, B, C$ and $D$ to complete the above statement with reference to $NCERT$ textbook.

Which of the following statements is correct about the mechanism of breathing?

What is the most important function of the diaphragm in mammals?

Which muscles help us to increase the strength of inspiration and expiration?

State whether the given statements are true or false.
$I.$ Ventilation in humans is an active process.
$II.$ Diaphragm helps in generating the pressure gradient in the lungs.
Choose the correct option.