Answer: I would go with B. Here’s why: An index fossil is usually easily recognizable, and underwent a wide geographic distribution. What leads me to believe B is the correct answer, is because it’s something that existed “ all over the world”.
There is a photo attached
Hope this helps ^_^
Answer:
Explanation:
In a lake, oxygenic phototrophs produce new organic material as well as O₂. If primary production rates are very high, the resultant excessive organic matter production can lead to bottom-water O₂ depletion from respiration and the development of anoxic conditions. This in turn stimulates anaerobic metabolisms, including anaerobic respirations and fermentations.
Organic matter that is not consumed in surface layers sinks to the depths and is decomposed by anaerobes.
Feral cats threaten<span> the survival of over </span>100<span> native </span>species in Australia<span>. They have caused the extinction of some ground-dwelling birds and small to medium-sized mammals. </span>
"Dissolved oxygen in seawater is used as an indicator of primary production (as its surrogate, so to speak) because the amount of molecular oxygen produced during photosynthesis is directly proportional to the amount of carbon fixed during photosynthesis, and determining the amount of dissolved oxygen is much easier to do."