紫菜的叶绿体中，除含有叶绿素外，还含有大量的[ ]
A．胡萝卜素
B．叶黄素
C．藻红素
D．藻黄素
答案：C
探头内（）的主要作用是防止产生杂波、使脉冲变窄、使盲区变小。
A.电缆
B.吸收块
C.保护膜
D.以上都不对
---Excuse me. Where is Lily?
---Oh, she _______ the volleyball match on the playground when I saw him just now.
A．watches
B．will watch
C．is watching
D．was watching
