One reason that multiple approaches are often taken to answer a testable question is that scientists

a.have different educational backgrounds and experiences. b.want to determine the single best way to find an answer. c.often look for the quickest way to answer the question. d.get tired of using the same approach every single time.

Well... I would say A.

But I would agree with almost all the choices because they are all possible situations.
On my opinion it is that scientists try to prove and test a theory, they end up finding evidence that proves the theory wrong or sometimes the theory is correct or the ones who test out the theory find the truth themselves.

have different educational backgrounds and experiences.

Plants, list any (wild animals)