【单选题】

{{I}}Questions 11 to 13 are based on the following passage.At the end of the passage, you will be given 15 seconds to answer the questions.Now listen to the passage.{{/I}} What do you think is the best title for this passage

A、How IsDiamond FormedAnd FounD、
B．Diamond--
A、Precious Stone.
C．Diamond Hunting.
Diamond-ProducingCountries.