What a Team Option Does
A team option gives an NBA franchise the ability to extend a player's contract for one more year at a previously agreed-upon salary amount. If the team chooses to use the option, the player must stay with that team for the additional year at that salary. If the team declines the option, the player becomes a free agent and can sign with any team. This decision is entirely up to the team's front office.
Why Teams Use Team Options
Teams include team options in contracts as a form of protection and flexibility. If a player gets injured, performs poorly, or the team's needs change, the team can decline the option and avoid paying that salary in future years. On the flip side, if a player performs well and stays healthy, the team can exercise the option to keep them at a below-market price. This gives teams control over their salary cap and roster decisions.
How It Affects Players
For players, team options create uncertainty because they do not control whether they will remain with a team. A player might want to stay but the team declines the option. Conversely, a player might want to test free agency but the team exercises the option and forces them to stay. Players often prefer player options instead, which give them more control over their future.
Example
For instance, if a player signs a four-year contract with a team option in year four, the team can decide by the deadline whether to keep the player for that fourth year at the agreed salary. If declined, that player becomes a free agent able to negotiate with other teams. If exercised, the player must play for that team at the set salary for year four.
Comparison to Other Contract Clauses
A team option is different from a player option, where the player decides whether to stay or leave. It is also different from a mutual option, where both the team and player must agree to continue. Team options give all the power to the franchise, making them valuable for teams managing their salary cap and roster composition. 
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