Concept:The opposite of a persistent attitude is an uncertain or unsteady one.Explanation:The word "dogged" means stubbornly persistent or tenacious.So its opposite should describe a lack of firmness or determination.In this sentence, Victor's support was dogged while other teachers' support was the opposite."Wavering" means becoming unsteady or uncertain, which contrasts directly with "dogged".The other options do not express this opposite idea clearly.Answer:C. wavering