input: The following are multiple choice questions (with answers) about medical knowledge.   **Question:** Anterior - posterior spread of implant is:   (A) Distance from center of most anterior implant to the center of most posterior implant   (B) Distance from center of most anterior implant to the distal surface of most posterior implant   (C) Distance from distal surface of most anterior implant to the mesial surface of most posterior implant   (D) Distance from mesial surface of most anterior implant to the distal surface of most posterior implant
output: ['(B) Distance from center of most anterior implant to the distal surface of most posterior implant <> answer', 'The following are multiple choice questions (with answers) about medical knowledge. <> instruction', '(A) Distance from center of most anterior implant to the center of most posterior implant  (B) Distance from center of most anterior implant to the distal surface of most posterior implant  (C) Distance from distal surface of most anterior implant to the mesial surface of most posterior implant  (D) Distance from mesial surface of most anterior implant to the distal surface of most posterior implant <> possible answers', '  Anterior - posterior spread of implant is: <> context']