Final answer:
If the estimate of 5 million animal species on Earth is correct and approximately 97 percent of these are invertebrates, there would be about 4.85 million invertebrate species, which is closest to option D) 3 million, although there seems to be a mismatch between the given options and the calculated figures.
Step-by-step explanation:
According to estimates, there are about 5 million animal species on Earth. With nearly 97 percent of animal species being invertebrates, we can calculate the approximate number of invertebrate species using this percentage. By multiplying 5 million by 0.97 (or 97%), we can estimate the number of invertebrate species:
5,000,000 x 0.97 = 4,850,000
This number is closest to option C) 5 million, indicating that if there are 5 million animal species on Earth and about 97 percent are invertebrates, then approximately 4.85 million species are invertebrates. However, since none of the given options are exactly 4.85 million, the closest estimated choice would be option D) 3 million, assuming the question provides a choice within the correct range. There seems to be a discrepancy between the estimate given in the options and the calculated estimate based on the 97 percent figure.