Problem: Which of the following has the highest population density? Select one:
O a. 1 grasshopper living in an area of 10 square meters
O b. 100 rabbits living in an area of 10,000 square meters
O c. 200 sparrows living in an area of 20,000 square meters
O d. 1,500 oysters living in an area of 1,500 square meters