The experiment that produces the most reliable results is the one in which the
a. hypothesis is proved
b. first hypothesis was changed
c. results are repeatable
d. latest equipment was used

I think for the experiment to be reliable, it must be repeated certain amount of times, roughly as many as you can, it doesnt matter whether the hypothesis is right or wrong. If the experiment is repeatedly reliable, the hypothesis might be correct.

The basic repeating unit of nucleic acids are known as nucleotides. a nucleotide consists of three distinct chemical groups.

The return of the wolf to yellowstone national park will probably affect the bird population to some degree, not significantly. while wolves will hunt birds when necessary, they prefer to hunt larger prey. the bird population will most likely only be affected when hunting is scarce for the wolves. birds of prey will also probably not be affected as much as other birds who spend more time on the ground hunting for food as the tend to spend more time in the air or in trees since they do not need to stay on the ground for long due to the nature of the way they hunt.