Many researchers think that monkeys are the most intelligent animals after humans. Scientist Irene Pepperberg has always wanted to show that other animals can be just as intelligent as monkeys. One day, as Irene was passing a pet shop on her way home, she decided to go in. She bought a one- year-old African grey parrot and called him Alex. 8.1.__ She wanted to show that birds don't have such small brains as people believe. She used a technique in which Alex could see her interaction with another human trainee. The parrot wanted to interact too, so it copied the behaviour of the trainee. 8.2.__ yummy stuff, it tried to follow the trainee's instructions. Because it liked eating During the intensive training, Alex learnt one hundred words, how to count to six, and how to give its preferences by saying what it did or didn't want to eat. 8.3.__ Alex built a really close relationship with Irene, who taught the bird for thirty years.

A. It could even say sorry. B. Alex liked flying in a large cage. C. It got a snack for every correct interaction. D. She began to train the bird every day because she had a plan.l​