Based on the slab rates for self-employment tax, Kristina's self-employment tax is "$7,650."
The self-employment tax rate for 2021 is 15.3 percent which is a summation of the 12.4% Social Security tax and a 2.9% Medicare tax on net earnings.
Given that the net profit of Kristina is $50,000
Therefore, the self-employment tax is calculated as
$50,000 × 15.3% = $7,650
Hence, in this case, it is concluded that the correct answer is $7,650
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