— The weekend is disappearing so fast! Let's look for some fun!   

—  _____. We really need some relaxation.  [ ]

A. That's a good point   

B. You can make it

C. Time is running out  

D. It isn't my cup of tea

在LC正弦波振荡电路中，不用通用型集成运放作放大电路的原因是其上限截止频率太低。