单选题 Complete the summary below using words from the box. Write your answers, A-H, in boxes 10-13 on your answer sheet.Though often doubted, the self-medicating behaviour of animals has been supported by an increasing amount of evidence. One piece of evidence particularly deals with 1, a soil-consuming behaviour commonly found across animals species, because earth, often clay, can neutralize the 2content of their diet.Such behaviour can also be found among humans in Africa, where people purchase 3at market stalls as a kind of medication to their illnesses. Another example of this is found in chimps eating leaves of often 4taste but with no apparent medicinal value until its unique structure came into light.A mineral B plants C unpleasant D toxicE clay tablets F nutritional G geophagy H harmless