“鸟类的黑手党”﹣﹣杜鹃，将自己的卵产到别的小鸟巢中，小鸟辛勤地为杜鹃孵卵并精心喂食杜鹃的雏鸟．对小鸟这种行为的解释，正确的是（　　）

①是先天性行为  ②是学习行为  ③是由遗传因素决定的  ④是由环境因素决定的．

    Jack Ma is the founder and CEO of the alibaba.com,____ is the biggest e-commerce company in China. The website is an English-language site. It aims to offer suppliers and consumers____ direct means to communicate, and thereby save time and money ____ (efficient). This model of business ____ (refer) to as B2B (business to business), and it has attracted millions of users worldwide. On the back of this success. Jack Ma and his team developed Taobao in 2001. Today, alibaba.com is considered by many to be one of the best B2B____ (site), with over 7 million users____ (come) from more than 200 countries and religions. Jack Ma____ (become) the first Chinese businessman to appear on the cover of the famous magazine Forbes in the past 50 years. Jack Ma is respected by people not just because of his success, but also because of his____ (person). Although modest, Jack Ma is a very ____ (ambition) man. When asked about his future plan, he once said, 'I believe that in the next ten years, ____ the top three Internet companies in the world, one will be from China—and we want to be that company.'