A biased sample is not a true sample of the population at large. For instance, a biased sample may include mostly women or mostly people under age 25.
A biased question reflects the questioner's viewpoint. This site gives examples of biased questions.
http://www.calvin.edu/~rpruim/courses/libarts-stats/I00/overheads/biased.shtml
what is the difference between a biased sample and a biased question
2 answers
a biased coin with P(H)=1/4 and P(T)=3/4 is thrown twice, find the probability of getting two heads