In this task, you are given a multiple-choice question and you have to pick the correct option. Answer with option indexes (i.e., "A", "B", "C", and "D").

Which of the following would have best aided a vessel at sea in crossing the sea in the 18th century? (A) A radar system (B) An old soothsayer (C) An experienced navigator (D) A crow's nest
C

You're most likely to encounter magma at (A) top of iceberg (B) a cloud (C) a space station (D) an island
D

If your were to sit still and stare at the sky for one of the earth's rotations, you will have wasted (A) half your existence (B) 1,440 minutes (C) your family's week (D) 2 days

B