According to Newton's law of universal gravitation, any two particles of finite mass attract one another with a force which is

• A. Inversely proportional to the product of their masses and directly proportional to their distance ap
• B. Inversely proportional to the product of their masses and directly proportional to the square of the
• C. Directly proportional to the product of their masses and inversely proportional to the square of the
• D. Directly proportional to the product of their masses and inversely proportional to their distance ap