Answer:
A: light availability
B: nutrients
Explanation:
Both nutrients and light availability affect the primary productivity of the freshwater ecosystem, therefore, scientists study both factors to track associated changes. This is because photosynthesis is driven by sunlight and nutrients availability. It is suggested that the abundance of autotrophs (e.g. phytoplanktons) in an aquatic ecosystem increases as light and nutrients availability increase. Thus, there will be more food available for secondary and tertiary consumers to feed upon. Resultantly, the aquatic environment will turn a biodiversity hotspot where many species of living organisms start dwelling. Thus, scientists mainly ecologists would focus on these two parameters at first that lead to consideration of other parameters.
For more information, you may want to read this scholarly article
https://aslopubs.onlinelibrary.wiley.com/doi/abs/10.4319/lo.2006.51.1.0288
Capsid is the component of a virus that is lacking in its cell
A capsid is the protein shell that surrounds a virus. Capsids functions by protecting the nucleic acids of a virus while interacting with the host environment. Capsids are made up of many oligomeric structural subunits that contains the protein; protomers. Capsids are generally grouped based on their structure. The common ones are helical and icosahedral.
The best and most correct answer among the choices provided by your question is the third choice or letter C.
Human activity is the primary cause of the rapid rise in loss of biodiversity.
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Selective breeding
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