Inexhaustible sources are:

Inexhaustible resources are the types of resources that are abundant in the atmosphere. Even if used carelessly, it cannot be removed from the earth by humans. 

They are a kind of renewable resource that is naturally produced by nature, not man-made. They are very important for the survival of living things on earth. They are used by plants, animals, and humans. They are essential for survival. 

One of the most important parts is that they are environmentally friendly and their use does not harm Mother Nature in the form of pollution.

Examples of inexhaustible water sources include air, water, and sunlight. Some of the inexhaustible sources of water, such as water, can be recycled. Some can be updated like sunlight. 

They help generate energy such as hydrothermal energy produced from water, solar energy generated from the sun, and wind energy generated from wind. The energy obtained from an inexhaustible source of energy is relatively cheap and free of contaminants. Therefore, the types of resources that have not been completed are inexhaustible.

Therefore, inexhaustible resources are not going to finish.

Hence, option A is correct.