Câu hỏi:

Read the following advertisement and mark the letter A, B, C, or D on your answer sheet to indicate the option that best fits each of the numbered blanks from 1 to 6.

SHEEP CAN RECOGNISE FACES!

    Many people think sheep aren’t very (1) ______ creatures. But in fact, according to new research, they may be cleverer than we think. For example, sheep can actually be trained to recognise human faces from photographs!

    Recognising faces is an important (2) ______. However, it seems that sheep are also social animals that can recognise other sheep as well as familiar humans. In experiments, researchers trained eight sheep to recognise the faces of celebrities from photographs. Training involved (3) ______ the sheep to make decisions about the photos (4) ______ they saw. At one end of a room, they would see two different photographs and would receive a reward of food (5) ______ approaching the photograph of the celebrity; if they approached the wrong photograph, they got nothing. Over time, they learned to (6) ______ getting food with the celebrity’s photograph. And after training, the sheep correctly chose the celebrity’s face eight times out of ten!

Many people think sheep aren’t very (1) ______ creatures.