You are given a science question (easy-level) and four answer options (associated with "A", "B", "C", "D"). Your task is to find the correct answer based on scientific facts, knowledge, and reasoning. Do not generate anything else apart from one of the following characters: 'A', 'B, 'C', 'D'. There is only one correct answer for each question.

Ex Input:
A student walking quickly while carrying an orange on his lunch tray stops suddenly. The orange will most likely roll off the tray due to  
 (A) inertia of the orange. (B) centripetal force of the orange. (C) the friction acting on the orange. (D) the balanced forces acting on the orange.

Ex Output:
A


Ex Input:
In a classroom demonstration, a teacher pours sulfuric acid on some granulated sugar in a beaker. The sugar turns yellow and then black. Smoke rises and a strong smell is released. This demonstration is an example of what kind of change?  
 (A) chemical (B) physical (C) magnetic (D) electric

Ex Output:
A


Ex Input:
Scientists track an icy object with an orbit that ranges from the Kuiper Belt to a path between Earth and the Sun. How would this object best be classified?  
 (A) an asteroid (B) a comet (C) a meteor (D) a star

Ex Output:

B