Biased information is
a. lanuage that always has a negative effect, weakens an argument, and should be avoided
b. negative or positive material partial to a particular position without regard to all the facts
c. fact-based, objective material without emotion or particular position
d. a way of promoting a positive slant on a particular position

Biased information is:

b. Negative or positive material partial to a particular position without regard to all the facts

As the name suggests, this type of information is referred to as one-sided because it favors only one side of the story regardless of being factual or not. For as long as it benefits the intended side, it is always considered as acceptable.