It can be inferred from the passage that limestone deposits serve as the basis of________.
Đáp án A
Thông tin ở câu cuối của bài: This type of algae has an essential role in the formation of coral reefs: it secretes lime from the seawater to foster the formation of limestone deposits.
How long does it take the children to walk to the golden sandy beach on foot?
You may borrow as many books as you like, provided you show them to ________ is at the checking desk.
The word contest in the last sentence could be replaced by___________.
Sarah delivered a/an ________ appeal to the court and asked for mercy.