In quiet breathing,

a. inspiration and expiration are both passive.
b. inspiration and expiration involve muscular contractions.
c. inspiration involves muscular contractions and expiration is passive.
d. inspiration is passive and expiration involves muscular contractions.
e. None of the answers is correct.

Explanation:

The process of moving air into and out of the lungs to facilitate gas exchange is called  Breathing. Air travels down the back of your throat and into your windpipe, which is divided into air passages called bronchial tubes.

Breathing: (i) Inspiration and (ii) Expiration.

Quiet breathing - The mode of breathing is the relaxed, normal breathing state that requires no control of any type. And it does not require the cognitive thought of the individual.

littering streams           is the answer

"menstrual cycle is a complex cycle that consists of several processes. order of occurrence of steps in menstrual cycle are as follows:

1. high progesterone levels maintain the endometrium lining of the uterus.

2. endometrium lining breaks down and low levels of estrogen stimulate the pituitary to release fsh and lh.

3. fsh and lh stimulates the follicles to develop and the oocyte to produce estrogen.

4. rising estrogen levels suppress fsh production and development of other follicles.

5. a spike in lh causes follicle to rupture.

6. a breakdown of corpus luteum causes progesterone level to drop."