Question

For Yoko's physical fitness class, she is supposed to do a certain amount of aerobic exercise on her own. Which of the following would be the best option?
1.Sit-ups
2.Push-ups
3.Lifting weights
4. Dancing

Answer 1

Pushups would be the best option. 
Sit-ups often require someone to hold the base of the legs stable. 
Lifting weights often requires a spotter. 
Dancing usually requires a teacher or a mentor.