Answer: Option B.
Explanation: Science only can answer things that are demonstrable.
For example, if someone says that in some cave in a distant planet, there is an old television with a sticker of a cat, this statement can't be proven right now, so this escapes the hands of the science.
Now, something abstract is an idea that you may obtain by abstraction, and one of the primary characteristics is that is "indetermined". Such as things as good, evil, religious subjects and more.
While you can find a paradigm where those things may be defined, this is more a philosophical approach, and these things usually can not be answered by science (you can't prove something if there is not an existent definition of that "something")
Note that a lot of ideas used in science, such as dark energy and things like that, are "kinda" abstract (and this is why there is not a lot of knowledge about them) but they are created by a logical approach.