Ap computer science question. I know the answer is B, but why though?

The valve seat performs two functions: it provides a seal for the valve in the combustion chamber, and it provides a cool surface to carry heat away from the valve. most valves use a seating angle.

The flashing of directional signals as it indicates that used it safe to bed

The color contrast between the open ocean and the lagoon between the spit and the mainland. the greater concentration of suspended sediments in the lagoon gives the waters a more turbid appearance. the source of sediment in the lagoon is (are) [(rivers and streams from the mainland) (wind-borne sediment from the spit) (ocean waves washing over the spit) (all of these contribute)].