Answer:
This question lacks options, options are: a. Keystone species b. Dominant species c. Competitor species d. Omnivore species e. Mutualistic species. The correct answer is a.
Explanation:
The most connected species from a trophic point of view in an ecosystem are keystone species, since their elimination has great effects on the stability and persistence of the network. The Keystone species are those species that play a crucial role in the structure and dynamics of a certain ecosystem and that, in the event of their disappearance, would be seriously unbalanced. These species are responsible for the physical structure of the habitats of many other species, and they play an important role in the succession processes of ecosystems. Elephants play an important role in maintaining the structure and balance of ecosystems in these communities, therefore they are keystone species.
In the society of clones, human clone lacks traits necessary for true independence from "parent" cells.
<u>Explanation:</u>
Clone can be defined as an individual organism that was grown from a single body cell of it's parents and that clone is literally identical to it's parent from which it has grown.
In this society, a human clone lacks traits necessary for true independence from the "parent" cells. There is also a contrast that whether a clone is entitled by contrast to feel that a parent cell is an appropriate parent cell or not.
I think it is b, please tell me if I’m wrong
Fossil is the remains of plants and animals.
Answer: B. Water breaks down into oxygen molecules for respiration.
Water is the required for photosynthesis, a process by which plants (terrestrial and aquatic) makes their food by utilizing water as a reactant to produce oxygen and glucose as product. The glucose act as a source of energy for conducting various metabolic processes in plants but oxygen is released in the air.

This oxygen is necessary for terrestrial and aquatic animals for respiration. Therefore, water breaks down into oxygen by the process of photosynthesis, hence water plays important role in respiration in living beings.