OG详解-OG1 文法 Q5

Choice B is the best answer. The convention being tested is the use of finite and nonfinite verb forms within a sentence. A main clause requires a finite verb to perform the action of the subject (in this case, “some historians”), and this choice supplies the finite present tense verb “claim” to indicate what some historians do.

Choice A is incorrect because the nonfinite participle “claiming” doesn’t supply the main clause with a finite verb. Choice C is incorrect because the nonfinite participle “having claimed” doesn’t supply the main clause with a finite verb. Choice D is incorrect because the nonfinite to-infinitive “to claim” doesn’t supply the main clause with a finite verb.