Questions 1 to 8 are based on the conversation you have just heard.

A．He had a broken leg.
B．He had a broken arm.
C．He was too scared to move.
D．He was too weak to move.

A．Because scientists like mosquitoes,
B．Because mosquitoes adapt quickly and can change their body chemistry.
C．Because the medicine against mosquitoes is of bad quality.
D．Because there are too many mosquitoes.