根据短文内容,从每小题所给的三个选项中,选出一个正确答案。

根据短文内容

      Dear classmates, I learned how to make dumplings last month. Let me introduce the steps of making dumplings to you.

      First, cut ____16____ the vegetables and the meat, and put them in a bowl.

      Next, add some salt and oil, and ____17____ them together.

      Then, put a ____18____ of filling ( 饺子馅 ) in a wrapper ( 饺子皮 ) and fold the wrapper around it.

      Finally, put the dumplings in the boiling water and cook ____19____ they are on the surface of the water. And then it’s time to enjoy them.

      I’m so ____20____ to share my way of making dumplings. Thanks for listening.

      16 . A . up B . off C . down

      17 . A . mix B . fix C . print

      18 . A . basket B . spoon C . box

      19 . A . though B . since C . until

      20 . A . angry B . happy C . bored