somE BirDs likE to sit on A shEEp BECAusE______.
A．thEy CAn EAt its pArAsitEs
B．thEy Enjoy trAvEling with thE shEEp
C．thEy DEpEnD on thE shEEp For ExistEnCE
D．thEy FinD thE position most ComFortABlE