旅游企业的基本竞争优势主要表现为()。

A．低成本

B．差异化

C．低价格

D．集中化

E．专业化

---I’m getting fatter and fatter. What should I do, doctor?

---You should eat ______ food and take ______exercise.

A．less, less

B．more, more

C．more, less

D．less, more