The first sentence lets us know that this passage is about （）

A．because they lay their eggs in mountain areas ______.
B．to give you a picture of how hard they work
C．to tell you that they like to climb
D．to tell you that mountain climbers are as slow as turtles

A．many turtles die while swimming to shore
B．female turtles protect their babies
C．once turtles leave land, they never return to the sea
D．the job of laying eggs takes tremendous strength