William is in the middle of swimming in a ten-mile race. He swims at a steady speed, and then slows down, stops to eat, swims faster to get back in the race, and returns to a steady speed. He later stops for water, and then again swims faster to get back in the race. Which graph best represents the situation?

A graph with time on the x-axis and speed on the y-axis. The graph is constant, decreases to 0, increases, is constant, decreases to 0, and then increases.

A graph with time on the x-axis and speed on the y-axis. The graph decreases, is constant at 0, increases, is constant, decreases to 0, and then increases.

A graph with time on the x-axis and speed on the y-axis. The graph is constant, decreases to 0, is constant, increases, decreases to 0, and then increases.

A graph with time on the x-axis and speed on the y-axis. The graph is constant, decreases to 0, is constant, increases, and then is constant.