Tides are observed around earth s
a. atmopshere.
c. mountains.
b. plains.
d. coastal areas.

d. coastal areas.

Explanation:

The tidal phenomenon is observed around the earth's coastal lands and the oceanic waters as they form a part of the hydrological cycle of the earth's ecological system, also these are important for the regulation of the nutrient flow and the motion of the bodies of water. They are of two types such as the high tides and the low tides. The high tides are those that are those that are created by the moon and the sun interactions with the earth and thus called the spring tides. While the low tides mostly due to the moon are called the Ebb or the neap tide. Geologically induced ties are caused by the earth's tectonic movements. Thus the tides and their origin is diverse and they may also be created by the movement of ship or submarines in oceans.

The answer is the magnetosphere.