Which of the following is not an outdoor game?

Concept: An outdoor game is a physical activity that is played in an open, unenclosed space (a field, court, park, or similar large area) and needs players to run, throw, kick, or otherwise move across that space, usually with team or open-field equipment. An indoor or tabletop game, by contrast, is played inside a room by a small group, typically seated, using cards, boards, or small hand-held equipment, and needs no large open playing area.

Application: Football is played on a large outdoor field (a pitch) by two teams who run and kick a ball across that field. Capture the flag is played across an extensive outdoor area, such as a field or wooded ground, where players run, hide, and defend territory to capture the opposing team's flag. Frisbee is thrown and caught in an open outdoor space such as a park or field, and needs room to run and track the flying disc. Uno, in contrast, is a card game played by a small group seated around a table with a standard deck of Uno cards — it needs no field, no running, and no outdoor space at all.

Cross-check: Testing each option against the outdoor-game criteria (open space + physical movement across terrain):

• Football — open field, two teams, running and kicking: satisfies the criteria.

• Capture the flag — large outdoor field or wooded terrain, running and hiding: satisfies the criteria.

• Frisbee — open park or field, throwing and running: satisfies the criteria.

• Uno — a seated card game at a table, no field or physical movement required: fails every criterion.

Since Football, Capture the flag, and Frisbee all satisfy the outdoor-game criteria while Uno does not, Uno is the one that is not an outdoor game.