Answer: B
Correct answer: has submitted
Neither, like either, each and none of the two, is singular, so it takes a singular verb: has submitted. The plural candidates standing immediately before the verb is what misleads the ear - it is the object of the preposition of, not the subject. The subject is neither, and a noun inside a prepositional phrase can never be the subject of the sentence. The same rule governs each of the boys is, one of my friends has, and every one of them was. Note that neither…nor follows a different rule when it joins two subjects: there the verb agrees with the nearer one, as in neither the manager nor the clerks were present. The other options fail on the same count - all are plural or continuous forms that cannot follow a singular subject.