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   Scientists think that many or most animals can't see colors. （1）

B

B

.To find out if dogs could see colors，scientists gave dogs food every time they played a certain piece of music. （2）

C

C

only when they heard this piece of music.They did not get ready to eat when they heard other pieces of music.
   Then the scientists gave the dogs food every time they showed them a certain color.The dogs got ready to eat when they saw this color. （3）

A

A

.Again the dogs got ready to eat.
   The colors were all the same to them. （4）

E

E

，however.For example if we put food in a red box and do this every day，a monkey will always go to the red box to get the food. （5）

D

D

if we then put food in a blue box.

A．The scientists then showed the dogs another color B．The world is black and white to them C．The dogs got ready to eat D．The monkey won't go to it E．Colors are not all the same to monkeys