I don't even get what they are asking.

Answer:
84
Explanation:
combinations
permutations
9 total number of objects
3 sample
nCr = ( n r ) = n!/(r!(n-r)!)
9C3
9!/(3!(9-3)!
9!/(3!*6!)
(9*8*7*6!)/(3*2*1)*(6!)
(9*8*7)/(3*2*1)
(3*4*7)/(1)
84/1
tutorial
https://www.tiger-algebra.com/en/solution/combination-without-repetition/c(9,3)/
gathmath
byjus