Which of the following statements is true? A. Only objects that are very close together exert gravitational forces on each other. B. Objects can only exert gravitational forces if they are at least as

Which of the following statements is true? A. Only objects that are very close together exert gravitational forces on each other. B. Objects can only exert gravitational forces if they are at least as dense as water. C. Only objects that are as large as planets exert gravitational forces on other objects. D. Any object with mass exerts a gravitational force on all other objects.