下列关于孟德尔研究遗传规律获得成功的原因的叙述，错误的是（　　）

根据语境和句意，从括号中选择一个可填入句子的正确选项，并将答案填写在答题卡上指定的位置。
（1）The cook added salt into the soup but it still wasn't____  enough. (salt, salty)
（2）The story book is interesting and it was____ by Mark Twain. (written, writing)
（3）“What do people in Korea do when they meet ____ the first time?” “They usually bow.” ( in, for)
（4）Singapore has a night____ , you can watch many kinds of animals there.(zoo, party)
（5）Every year, Guiyang attracts larger numbers of tourists, ____ in summer.( especial, especially)