题目内容：
根据材料，完成题。German zoologist Randolf Menzel says bees aren't as busy as people believe they are．
"Bees are not particularly 76 ． Instead they sleep a lot and are lazy． They spend 77 80 per cent of the night sleeping． Even during the day they often fly to the nest78 they rest their wings． " said Menzel, a zoologist at the Free University in Berlin, who has studied bees for four decades． But to 79 for their apparent laziness, they are actually very intelligent． They are 80 learners and able to recognize various smells．
Menzel said bees' learning, like 81 of many animals, was based on a reward sys-tem．"If a bee is rewarded once for something, it remembers it for a week． But if it is re-warded three times, it will remember it for its 82 lifetime． " Said Menzel． He last week was awarded a 83 by the German Zoological Society．
The memory capacity of bees means they can 84 among more than 50 different smells to find the one they want． "What is interesting is that what smells good to a bee, is also a 85 smell for humans． " said Menzel．
请在第__(76)__处填上正确答案。 A．working hard
B．hardworking
C．hard working
D．working hardly
参考答案：
答案解析：