单选题 I saw a lot of children playing in the garden, most of them ＿＿＿＿＿＿＿＿ girls. 的答案

成人教育远程网络教育函授网上考试【专科英语II】课程在线考试模拟试题正确答案解析，免费查看【专科英语II】作业答案。
题目内容：
I saw a lot of children playing in the garden, most of them ＿＿＿＿＿＿＿＿ girls.
题目选项
are
were
being
have been

参考答案价值：100%