His command were so peremptory that we felt humiliated.

Answer: Option C

Specious : superficially plausible, but actually wrong.
Poignant : evoking a keen sense of sadness or regret.
Dictatorial : of or typical of a ruler with total power.
Rough : having an uneven or irregular surface; not smooth or level.
Peremptory : insisting on immediate attention or obedience, especially in a brusquely imperious way.

Synonym of Peremptory is Dictatorial