Question 39. The word they in paragraph 3 refers to ______ .

Từ “they” trong đoạn 3 đề cập đến ______. Thông tin: The California condor is another accidental victim of human activity. These huge birds with bald heads and big beaks weigh up to fourteen kilos, have a wingspan of up to two metres and can live as long as sixty years. They play an important role in the ecosystem by feeding on dead animals, thus preventing the spread of disease. → Chọn đáp án B