The American civil rights movement started in the mid-1950s. A major catalyst in the push for civil rights was in December 1955, when NAACP activist Rosa Parks refused to give up her seat on a public bus to a white man. Read about Rosa Parks and the mass bus boycott she sparked.
I’ve never read this story but my gut is going with A
I'm guessing you're identifing the verb in this sentence in that case the answer would be:
can be considered
Major.
Because the subject of the sentence is "I", "major" is the subject compliment.
I hope I helped! :))
