Subject :NSO Class : Class 7
During the process of inhalation in human beings _________.
(A) Diaphragm contracts but external intercoastal muscles and lungs expand.
(B) Diaphragm expands but external intercoastal muscles and lungs contract.
(C) Diaphragm and external intercoastal muscles expand but lungs contract.
(D) Diaphragm and external intercoastal muscles contract but lungs expand.