Given that metal oxides such as $Cr_2O_3$ and $Mn_3O_4$ cannot be reduced using Carbon or Carbon monoxide, which of the following must be true?

Question

(1) This is because $Al$ is more electropositive than $Cr$ and $Mn$

(2) This is because $Al$ is more electronegative than $Cr$ and $Mn$

(3) This is because the impurities have lesser affinity for $Al$

(4) None of the above

(a) (4)
(b) (1) and (2)
(c) Only (1)
(d) Only (2)