the process in which exchange of gases takes place is called 
option a] combustion
option b] respiration
option c] breathing
option d] cellular respiration 

Dear Student,
The process in which exchange of gases takes place is called (c) breathing.
Breathing consist of inhalation and exhalation. Inhalation means taking air in, to get oxygen and exhalation means expelling air out to release carbon dioxide. A breathe means one inhalation and one exhalation. It involves the movement of ribcage and diaphragm.
Regards