The following reaction involves the thermite reduction,

$4A{l}_2{O}_3+3Mg\to 3MgA{l}_2{O}_4+2Al$

${\mathrm{Cr}}_2{\mathrm{O}}_3+\mathrm{Al}\stackrel{\mathrm{\Delta }}{\to }2\mathrm{Cr}+{\mathrm{Al}}_2{\mathrm{O}}_3$

Thermite process refers to the reduction of metal oxides with aluminum powder that produces a large amount of heat.

A thermite reaction may start if a ship having alluminium parts is hit by a missile.

Hence, option A, C and D are correct.