A、 How insects breed in extreme desert temperatures.
B、 Different types of beetles.
C、 Poisonous plant in desert.
D、 How beetles can defeat a plant's defense system.

【正确答案】 D

【答案解析】解析：主旨题。讲座中提到But a recent study has found one insect,a beetle，that can chew its waypass the plant’sdefense system by cutting the mainly vein that delivers the poison to the leaves．即“但最近的一项研究发现，一种昆虫，即甲虫，可以通过切断传递毒物到树叶的叶脉的方式来通过植物的防御系统”。因此，正确答案为D。

A、 Its resin(树脂)isn't poisonous.
B、 It can shoot its resin a great distance.
C、 Its leaves have no veins.
D、 It doesn' t need much water to grow well.

【正确答案】 B

【答案解析】解析：细节题。讲座中提到This is about a desert shrub whose leaves can shoot up a stream of poisonous resin adistance of six feet．即“这是关于沙漠灌木的，它的叶子喷出的有毒树脂流达六英尺之远”。因此，正确答案为B。

A、 By cutting a path all the way across the leave.
B、 By eating only the stem of the plant.
C、 By changing the plant' s chemistry.
D、 By eating only at night.

【正确答案】 A

【答案解析】解析：细节题。根据Another is by cutting a path all the way across the leave to hold the flow of chemicals．Thenthey simply eat between the veins of poison．可知甲虫还可以通过切断整个叶片来阻止毒素的流动，只吃在有毒叶脉之间的叶片。因此，正确答案为A。