In a high-pressure system,

a.

air molecules are far apart and pressing on Earth's surface.

b.

air molecules are far apart and rising away from Earth's surface.

c.

air molecules are close together and pressing on Earth's surface.

d.

air molecules are close together and rising away from Earth's surface.

High-pressure means that the molecules of a substance will be compressed (pushed closer together). A high-pressure system forces the molecules against whatever surface is closest to them.

Therefore, the answer is C.

The correct answer is option c. air molecules are close together and pressing on Earth's surface.

Explanation:

The weight of air that exists on the atmosphere and that is around us is called air pressure.

If this air is in a high position of the atmosphere, this pressure will decrease, because there are fewer air molecules above, so they exert less weight and less pressure.

This pressure will not be the same every day, because the Sun does not always heat the Earth in the same way. Since the hot air rises, the places where there is greater warming by the sun will have low pressure.

In a low pressure system, the center has the highest concentration of low pressure, more than the surrounding area.

And in a high pressure system, the center will have a higher concentration of high pressure. This means that the wind blows away from high pressure, swirling in the opposite direction to a low pressure system.

This type of air pressure will be determined by temperature and pressure.