What is the rule for the following sentence? He's the kid (who/that) beat my Pokémon score.

A. If you are Iggy Azalea, use them both. "Now tell me, who that, who that?
That do that,
do that?
B. Use "who" when referring to people. Use "that" when referring to objects or animals.
C. Always use "that" as the option. You'll only be wrong half the time. If in doubt,
mumble.
D. Use "that when modifying a verb; use "who" when modifying a noun.