Well, biotic factors are living things in an ecosystem such as animals or insects. Abiotic factors are non living things in an ecosystem such as sunlight or temperature. I would say biotic factors would be more harmful since this includes bacteria or other diseases, not many abiotic factors would pose a great threat to the entire human species. Hope this helped.
The correct answer is option A, that is, saturated.
The mentioned lipid is not a phospholipid, as it does not comprise a phosphate group at the terminal of the chain, and is not a triglyceride due to the absence of glycerol moiety.
Each carbon combined with the hydrogens forms the maximum number of possible C-H bonds, thus, there are no multiple bonds between the carbons. Hence, it can be concluded that the lipid is saturated.
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.
The answer that seems like would best fit this graph would be "(4)Years"