Definition: You are given a question on conceptual physics. You are also given 4 answer options (associated with "A", "B", "C", "D"), out of which only one is correct. You need to answer the question by selecting the correct option. You should only answer with the choice letter, not the whole answer.
Input: According to Coulomb, a pair of charged particles placed twice as close to each other experience a force
(A)twice as strong (B)four times as strong (C)half as strong (D)one-fourth as strong

B