Why was he late

A．They may be homesick and feel insecure.
B．They are either cold or very sick.
C．They may try to attract other people"s attention.
D．They want to protect themselves from physical injuries.

A．Many species have moved further north.
B．Many new species have come into existence.
C．Many species have developed a habit of migration.
D．Many species have become less sensitive to climate.

A．Eight.
B．Seven.
C．Nine.
D．Two.