Question 2 Which of the following correctly describes what a mutation is?

A). A change in the DNA code of an organism

B). A change to a gene of an organism

C). A change to the nucleotide sequence

D).All the above

Why is it important for scientists to review and repeat the work of other scientists? 1.a scientific theory must be tested three times before it is proven. 2.the scientific method only applies to repeated experiments. 3.an experiment may have had errors that the scientists didn't recognize. 4.the results of individual scientists may be influenced by bias. 5.an experiment must be performed twice before the data can be analyzed.