B) Neither the coach nor his players knows whether or not this season will end in a championship ring or not.
This sentence is incorrect. The subject of the sentence is neither the coach nor his players. The verb that doesn't agree is knows. Knows agrees with a singular subject. The subject is plural. When the coordinating conjunction neither nor is used, the verb must agree with the option closest to the verb - in this case players. Players is a plural subject so knows should be know.
