Video solution:

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Written solution:

Let us assign everybody $2$ apples. This leaves us with $24 - 3 \cdot 2 = 18$ apples.

Then, we want to solve $$a + b + c = 18,$$ where $a, b, c$ are the additional apples given to Alice, Becky, and Chris.

Note that these are all nonnegative, since we already satisfied the only condition we needed to.

We can use stars and bars to get the number of solutions as $$\binom{18 + 3 - 1}{3 - 1} = \binom{20}{2} = 190.$$

Thus, the correct answer is C.