<span>B. The algae and the spider crabs have a mutualistic relationship
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<span>E. The spider crabs are parasites of the algae.
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Physical Factors:Physical factors that affect population distribution include altitude and latitude,relief,climate,soils,vegetation,water and location of mineral and energy resources.
Answer:
If all frogs were to die off, a valuable food source will go missing in the food chain of many animals around the world after that the number of animals that eat the frogs will die off, then the animals that eat them will go hungry, and their populations will be devastated as well.
The answer is A
If not then its C