Task: Question Answering
Input (English): Where do most short-period comets come from and how do we know?
(A)The Kuiper belt; short period comets tend to be in the plane of the solar system just like the Kuiper belt. (B)The Kuiper belt; short period comets tend to come from random directions indicating a spherical distribution of comets called the Kuiper belt. (C)The asteroid belt; short period comets have orbital periods similar to asteroids like Vesta and are found in the plane of the solar system just like the asteroid belt. (D)The Oort cloud; short period comets tend to be in the plane of the solar system just like the Oort cloud.
Output (English): A