Biology is applied Chemistry which is applied Physics. I prefer Physics but I like all sciences.
sci·ence   [sahy-uhns]
noun
1.
a branch of knowledge or study dealing with a body of facts or truths systematically arranged and showing the operation of general laws: the mathematical sciences.
2.
systematic knowledge of the physical or material world gained through observation and experimentation.
By that logic, physics is simply applied mathematics.
By that logic, physics is simply applied mathematics.
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I show the most prowess in chemistry (indeed I finished highschool with it as my highest ranked subject) however I don't think there is one "best" science. I voted chemistry, but I think the question should be reworded.
Also: biology IS a real science. A damned important one at that. A definition:
I obviously do regard it as a real science. I edited two parts of my OP to make me seem like less of an idiot.
I'm not trying to be a dick, but honestly, your original post said "obviously biology isn't a real science" or something very close to that, so it appears you did not regard it as a real science. I was going to post something close to what Swan did, because that's an absolutely ridiculous and ignorant statement to make, unless you don't actually know what the definition of science is.
On topic, there are more sciences than the three you've listed, however, out of those three I'm most interested in biology (no science is "the best science"). I do very much like chemistry and physics and enjoyed studying them in high school and college, but I've just always been very interested in various biological subjects.

