Final answer:
Features like positions, winners, and teams are not present in all games, as some games are cooperative, single-player, or not structured with these elements. Moreover, decisions in games tend to vary with the changing situations within the game.
Step-by-step explanation:
The features that are not common to all games are:
- C. Positions
- D. Winners
- E. Teams
While all games have properties (A), such as a set of tools or conditions, players (B) who participate in the game, and rules (F) that govern how it is played, not all games necessarily have positions, winners, or teams. For example, cooperative games may not have winners or are designed in such a way where all players win or lose together. Puzzle games might not have specific positions for players, and solo games do not involve teams.
To address the related query, in any game, one would expect that decisions will vary as the situation varies (answer a). This is because each game presents unique circumstances that require players to make strategic decisions based on the current state of the game and not on external factors like the time of the year, location, or day of the week.