省略 — 英语选择题
题目
在介绍海滨主题公园时，哪一项正确地省略了与主句相同的主语和 be 动词？A. While visitors are walking along the coast, they can see seabirds. B. While walking along the coast, visitors can see seabirds. C. While visitors walking along the coast, they can see seabirds. D. While walking along the coast, seabirds visitors can see.