Sahil surveys 50 randomly selected people at the city park to find their favorite activities. how might the sample be biased?

not everyone in the city lives near the park.

people at the park might be more likely to prefer outdoor activities to indoor activities.

the 50 people he surveyed might not visit the park every week.

people at the park might be less likely to have a favorite activity.

Well, the answer quite stands out
First, Biased means how might it be "inaccurate", or in what ways could it be leaning more to one side than another, etc
Like if you ask a bunch of old people at a nursing home: "What's your favorite video game?" Well, chances are most of them don't want anything to do with video games, so that would be biased.

Well, same thing here. If you go to a park, chances are your not going to find a whole lot of people who like indoor activities better than outdoor.
So, by going to a PARK for your survey, your biased, because this particular survey is about favorite activities, and if your at a park, practically nobody will say something about an indoor activity being their favorite.

Meaning, your answer is B