The following are multiple choice questions (with answers) about medical knowledge.   **Question:** Which of the following structures is not of ectodermal origin:   (A) Hunter-schreger bands   (B) Enamel spindles   (C) Enamel tufts   (D) Enamel lamellae
['(B) Enamel spindles <> answer', 'The following are multiple choice questions (with answers) about medical knowledge. <> instruction', '(A) Hunter-schreger bands \n (B) Enamel spindles \n (C) Enamel tufts \n (D) Enamel lamellae <> possible answers', '  Which of the following structures is not of ectodermal origin: <> context@']