Most living things need oxygen to survive. you breathe in oxygen and it is carried to this organ. here the red blood cells pick up the oxygen and carry the oxygen to all the body cells that need it. what is this organ?
a) diaphragm
b) heart
c) lungs
d) trachea

The correct answer would be the C) lungs.

Lungs are the pair of air-filled spongy organs.

They are mainly associated with the exchange of gases (carbon dioxide and oxygen) in the body.

The alveoli are the group of tiny air-sacs present in the lungs which form the site of gas exchange.

The oxygen from the alveolar site diffuses into the blood and carbon dioxide from the blood diffuses into the alveolar site.

The oxygen is then transported to all cells of the body with the help of circulatory system whereas carbon dioxide is removed out of the body as a part of exhaled air.

d concave shape of wave rock

explanation:

the concave shape of wave rock is a very good evidence that supports the evolution of earth due to chemical weathering. if we talk about structure of   wave rock, studies have estimated that it is around 2.7 billion years old. it also serves as the foundation of evidence that it was the place where australian continent began to form.

how the structure of wave rock was created?

studies suggest that structure of wave rock was created when the surrounded area was started to weather due to which deposition of material started on the part of land which now contains wave rock.

the structure of wave rock is considered to be one of the best-known landforms in australia. at the height of around 15 cm, there can be found flared slopes which formulate the margins of hyden rock. it is now assumed by geologists that wave rock was created by subsurface water-induced weathering and not by glaciers, waves or wind.

due to deposition of material over the period of long time, the wave rock became tougher and tougher due to weathering from surrounding terrain. this makes it a physical evidence that supports   the evolution of earth due to chemical weathering.

hope it !