Nhận biết (M1)

Domesticated thousands of years ago in South America, the avocado deviates structurally from the wild plant it is descended from. Summer squash, another domesticated crop from the Americas, doesn't closely resemble any wild plant, and genetic research only recently __________ its ancestor to be the wild Johnny gourd.

Which choice completes the text with the most logical and precise word or phrase?

• A.

  encouraged

• B.

  expanded

• C.

  petitioned

• D.

  revealed