Concept:After the word “all,” the correct relative pronoun is “that,” not “what.”Explanation:The sentence uses “all” as an antecedent, meaning everything He said.In formal English, “all” is followed by the relative clause connector “that.”Saying “all what He said” is ungrammatical because “what” already means “the thing which.”Therefore, the phrase should be “all that He said,” making option D the correct choice.Answer:D. that