Given :

So, according to the given data, we will check the options:
(i) 13 ∈ C : False because 13 is not one of the numbers of the group C
(ii) 6 ∉ A : True because 6 is not one of the numbers of the group A
(iii) 9 ∉ A : False because 9 is one of the numbers of the group A
(iv) 24 ∈ C : True because 24 is one of the numbers of the group C