法的要素是指法律有哪些基本因素或元素构成，一般认为法律由（）、法律原则和法律概念所构成。

A. Sure. What is it
B. It’s very nice of you to say so.
C. It’s nothing.
D. Have a nice trip!
E. Certainly. Here you are.

A:I’m sorry to have kept you waiting for so long.
B:______ I’ve been killing time by listening to music.