A sentence starts with a noun or a pronoun. A gerund (verb+ing) is used as a noun. In the given options, Judge is a verb, to become a noun it requires an article ‘the’ with it. It should have been ‘the Judge’ to start the sentence. ‘Judged’ is an adjective. ‘Judging’ a gerund acts as a noun. ‘Judging’ is the correct answer.