题目内容：

    Humans may have been enjoying cacao, which has been used to make chocolate, for much longer than experts had thought.

Researchers at the University of British Columbia in Canada have found that humans grew cacao trees and consumed (食用) cacao starting around 5,300 years ago.

The researchers found evidence of cacao’s use at an ancient village in the highlands of southeastern Ecuador. They examined the remains of very old objects. The village was part of the Mayo-Chinchipe culture of the Andes.

Scientists had already mostly agreed that cacao was first domesticated in South America instead of Central America, as they once believed. But the new discovery shows cacao was grown about 1,500 years earlier than was known before.

The University of British Columbia researchers also identified (证实) a substance found in the cacao tree but not in its wild relatives. This suggests that humans grew the tree for food purposes.

Today, the seeds are cooked and turned into many chocolate products.  But thousands of years ago, cacao was used to make drinks.

Michael Blake is a professor of University of British Columbia who helped lead the study. He said that the objects on which cacao was found suggest a lot about how people used the substance at the time.

“They clearly drank it,” Blake told the Reuters news service.

There is no clear history of native populations in South or Central America using cacao to make chocolate the way people do now, the researchers reported. Native populations in the upper Amazon area today still use cacao to make special drinks, they added.

Evidence suggests cacao growing moved into Central America and Mexico about 4,000 years ago. It is not clear how cacao’s use spread between South and Central America.

But by the time Spanish explorers arrived in Central America in the late 1400s, people were using it to make hot and cold chocolate drinks with spices.

By the 1580s, Spain began importing cacao and spreading it to other European countries. By the 1800s, technology developed in the Netherlands made it possible to turn cacao into a solid chocolate product.

1.Where was cacao grown earliest?

A.Mexico. B.Canada

C.Central America. D.South America.

2.When it comes to the introduction of cacao to Europe, which country contributed most?

A.America. B.Canada.

C.Spain. D.Netherland.

3.Which of the following can serve as a best possible title for this passage?

A.The history of cacao. B.The home of cacao.

C.The use of cacao. D.The spreading or cacao.