Although this is lacking information, I can tell you that the word Biased means going against something, basically meaning they do not like it.
Someone that has a 'Biased' opinion means they are supporting one side, and they do not like the other.
The answer may have the writers opinion based on the text you read.
As the question asks, "which of the following is true, I assume this means that the answer you are looking for will include the writers opinion, so make sure it matches what you think the writer is going against and for.