The ecosystem is the lowest level of the biosphere hierarchy to include
a.
the animal species present
b.
weather patterns and soil conditions
c.
interactions between different species
d.
the plant species present

The ecosystem is the lowest level of the biosphere hierarchy to include weather patterns and soil conditions.

Ecosystem includes everything that is necessary for living. Its include the environment, air, water, soil and energy. Ecosystem is a closed system. It has the ability to continually renew itself.

answer; ///i believe the correct answer is (aids) acquired immune deficiency syndrome;

estuaries are the partially enclosed coastal bodies of brackish water formed at the mouth of sea where river meets an ocean. it is a transition zone between river and sea water so estuaries are influenced to both marine environment such as tides, waves and to riverine such as flow of fresh water and sediments. the mixing of sea and fresh water provide high level of nutrients, making estuaries a high product habitats.

many estuaries suffers degradation from a variety of human activities like erosion from deforestation, overgrazing, overfishing, drainage and eutrophication.

so from the above statement answers will be

1. false as estuaries are formed due to both brackish and freshwater.

2.true, due to high productivity estuaries are breeding ground for many marine species.

3. direct and indirect activities of man that contribute to pollution and deposition of sediments.