①量入为出、适度消费原则
②勤俭节约、艰苦奋斗原则
③避免盲从、理性消费原则
④保护环境、绿色消费原则
A:①②③④
B:①②③
C:①②
D:①
When you see an English film or talk with native speakers, observe their facial expressions and g____.