Correct option is C
The part that contains an error in the sentence is (c) our soldiers have being.
The correct phrase should be "Our soldiers have been" instead of "have being."
"Have been" is the correct verb tense to indicate an action that started in the past and continues into the present. In this case, it means that the soldiers started making a clean sweep of the sheep and poultry in the past, and they are still doing it.