单项选择题
A．he wanted to help support his family B．he needed money for school C．he had to pay back a student loan D．he did not have enough pocket money
A．the Arctic Summer B．Marmots and Squirrels C．Keeping Warm in the Arctic D．Freezing Temperatures
A．the Indianapolis 500 B．a new kind of car C．an early auto race D．the streets of Chicago