More American people take their troubles with them on holiday, according to a new survey.    31         40 percent said that the main reason for going away is to escape   32          (press) from work, almost all said they worry more      33          they do at home. Only four in every one hundred said that they are happy and free of care.

The most common worry is burglary（入室盗窃）, with four out of ten worrying about their homes   34        (break) into while they are abroad. More than a quarter feel they will feel crazy   35     some other noisy and rough holiday-makers and twenty-two percent worry they may be attacked  36           their possessions will be  37            (miss).

The survey also showed   38         the stay-at-home Americans are no more. Three out of every five want to have a holiday abroad, which was          39    increase from the figures only three years ago. The hotel holiday is still a winner, with about one third of all Americans   40          (prefer) to go on a self-catering（自助） holiday.

水蒸气蒸馏法最适宜提取的化学成分是（）

A.多糖

B.黄酮

C.皂苷

D.生物碱

E.挥发油