Well, Velocity is the speed of something in a given direction, and speed is the rate at which someone or something is able to more or operate. They both invlove speed, so this is a hard one, but I wold say either B or D
<em><u>This</u></em><em><u> </u></em><em><u>it</u></em><em><u> </u></em><em><u>you</u></em><em><u> </u></em><em><u>can</u></em><em><u> </u></em><em><u>do</u></em><em><u> </u></em><em><u>it</u></em><em><u> </u></em><em><u>boy</u></em><em><u> </u></em><em><u>or</u></em><em><u> </u></em><em><u>girl</u></em><em><u> </u></em>
<span>Earth (and hence the observer) moves.</span>