Biological classifications have changed over the years. what is probably not a reason for these changes?

a. scientists change the names of taxonomic groups to match current nomenclature.

b. scientists learn more about the genetic sequences of organisms, and thus how they are related.

c. scientists learn more about the evolutionary histories of organisms through the fossil record.

d. new species are discovered that challenge old classifications.

I'm sorry I don't have the answer. but I don't want you to get it wrong, it is not D.

the speed increase from w to x due to increased gravity force

the speed decreases from x to y due to decrease in gravity

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