Several good choices.
Depends upon several factors.
How much do you plan to spend?
The lens depends upon where you are standing/sitting.
Any particular sport?
The typical basketball settings will be about f/2.8, 1/640th second, ISO 3200.
If you are on the sidelines you only need about 50 to 85 mm focal length.
If you are way up in the stands, you need 200 mm or more.
Just remember, you must (must) turn-off your flash.
What would be a good Nikkon DSLR Camera for Indoor Sports photography.

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