The following are multiple choice questions (with answers) about medical knowledge.   **Question:** The principal reason for placing an aluminium filter in the primary beam of radiation is to:   (A) Reduce exposure time   (B) Decrease development time of the films   (C) Reduce radiation to the skin of the patient   (D) Obtain greater definition of the images of teeth
['(C) Reduce radiation to the skin of the patient <> answer', 'The following are multiple choice questions (with answers) about medical knowledge. <> instruction', '(A) Reduce exposure time \n (B) Decrease development time of the films \n (C) Reduce radiation to the skin of the patient \n (D) Obtain greater definition of the images of teeth <> possible answers', '  The principal reason for placing an aluminium filter in\nthe primary beam of radiation is to: <> context@']