An irregular verb is one that does not form its simple past tense or its past participle by adding "-ed" or "-d" to the base form. Irregular verbs contrast with regular verbs, which form the simple past tense and past participle by adding "-ed" or "-d."
The following that is a modifier is C, an adjective and an adverb.
Explanation:
The characters become paranoid and fear one another, so they plot and blame one another rather than using rational thinking.
