It’s answer C because of eutrophication
Answer:
E. It takes a picture of the brain according to oxygen levels. More oxygen in an area indicates more activity in that area.
Explanation:
Haemoglobin is diamagnetic when oxygenated but paramagnetic when deoxygenated. This distinction in magnetic characteristics leads to tiny variations in the blood MR signal. Since blood oxygenation differs, these variations can be used to identify brain activity depending on the concentrations of neural activity.
<span>The correct answer is B) choose the correct lane. It is always important when driving to ensure you are in the correct lane, but in roundabouts, it is essential to the traffic flow. Choice A is not correct because roundabouts are designed to slow down traffic and you need to be paying attention to what is going on and slowing down before you enter. Choice C is not correct because you do not have the right-of-way; the traffic already in the roundabout does and you would need to yield to them. Choice D is not correct because choices A and C are not correct.</span>
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.