Answer:
the correct answer is number (1)
Step-by-step explanation:
this number is the one who refers to the continental shelf because as you can see it refers to an area which is a shallow water area and near from the continent . and the continental shelf is exactly this area , it is defined as a continent which is under an area of a shallow water of the sea which we can called shelf sea
number 2 refers to continental slope and it defines as the steep slope which connect between the continental shelf and the sea floor