从A、B、C、D四个选项中，选出可以填入空白处的最佳选项，并在答题纸上将该选项标号涂黑。
1. I advise you to stay away from Maria. Although she is usually easy-going, she ________ quite annoying sometimes.
A. can B. may C. must D. should
2. Recognized as ________ world cultural heritage by the United Nations in 2002, paper cutting is ________ practice which originated in ancient China.
A. the; a B. a; a C. the; the D. a; the
3. Although chatting on line has exploded in popularity in recent years, there is no ________ for a face-to-face conversation.
A. privilege B. affection C. substitute D. adjustment
4. How old you grow is a factor that you can influence, ________ that is determined by your lifestyle.
A. what B. one C. something D. anything
