单项选择题
A.lower ballast tanks are filled with water B.sea anchor is deployed to windward C.fuel tanks are not less than half full D.passengers are strapped to their seats
A.the surface of the sea B.high waters and low waters C.all low waters D.the lower of the two daily low tides
A.Central North Atlantic Ocean B.Caribbean Sea C.Western North Pacific Ocean D.area off the west coast of South America