先通读下面的短文，掌握其大意，然后根据短文内容和所给首字母，在空格内填入一个适当的词，使短文意思完整。所填单词在题后横线上必须完整写出。

Wendy tells me something about Halloween in her e-mail. I know a l  1  about Halloween now. People in the USA have a Halloween party on O  2  31st. Children play a game called ‘trick or treat’. They knock on n  3   doors and shout ‘trick or treat’. Usually people give children a treat of some candies.

They wear s  4  costumes and masks. Sometimes they p  5  their faces. It is w  6  .

At Halloween, they have hot drink and eat lots of food. They do not eat mooncakes.

标准宇宙模型最开始提出来是在：（）

A．20世纪30年代

B．20世纪70年代

C．20世纪80年代

D．20世纪90年代