Which statement about capillaries is correct?
a. their walls are only one cell thick
b. they move mucus through the lungs
c. their walls are covered with cilia
d. they warm and humidify inhaled air

Option a.

Explanation:

Cappilaries are thin, branched blood vessels that make network between venues and atrioles.

There main function is to transfer oxygen and nutrients from blood to other body part and to collect waste products from different tissues.

Cappilaries show presence of thin walls, made up of only one cell that help them to perform their function efficiently.

Thus, the correct answer is option). a.

false because ozone (o3) depletion does not cause global warming, but both of these environmental problems have a common cause: human activities that release pollutants into the atmosphere altering it.

global warming is caused primarily by putting too much carbon dioxide into the atmosphere when coal, oil, and natural gas are burned to generate electricity or to run our cars.

explanation: