Why are some signs of a healthy rainforest harder to spot?
Animals in a rainforest can be difficult
for scientists to find.
D
Some species in a rainforest look like
different species.
Rainforests have too many resident
animals to count.
Scientists studying rainforests can get
lost in dense areas.
I need the answer ASAP

A. Animals in a rainforest can be difficult  for scientists to find.

Explanation:

According to the article about the "Rainforest" you've attached, a reason why a healthy habitat is harder to spot in a rainforest is due to the "density of the rainforest." This density makes it harder for the scientist to find the animals because the animals remain hidden in it. Animals can easily adapt to such niche by camouflaging or doing other similar strategies to remain hidden. This makes it harder for the scientists to tell the well-being of the animals.

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