4)As presented in this chapter, when looking at energy use per capita in other places around the world that are beautiful and where people live happy, modern lives (the chapter focused on Europe), the key difference between life in those places and in the United States is (are): a. Europeans tend to drive more energy efficient vehicles. b. Gasoline in the U.S. is much more expensive than it is in Europe. c. U.S. cities are more suited for walking. d. Europeans drive more than we do in the U.S. e. All of the above f. A and B