单项选择题

Questions 13 to 16 are based on the following passage. At the end of the passage, you will be given 20 seconds to answer the questions.
Now, listen to the passage.

How can sharks find their quarries

A.By good sense of water waves made by quarries.
B.By good sense of smell and electrical magnetic power.
C.By good sense of light.
D.By good sense of blood.