A rectangular field is 300 feet wide and 400 feet long. Random sampling indicates that there are, on the average, three ants per square inch through out the field. [12 inches = 1 foot.] Of the following, the number that most closely approximates the number of ants in the field is<spanclass=′latex−bold′>(A)</span>500 thousand<spanclass=′latex−bold′>(B)</span>5 million<spanclass=′latex−bold′>(C)</span>50 million<spanclass=′latex−bold′>(D)</span>500 million<spanclass=′latex−bold′>(E)</span>5 billion