A rectangular loop of wire and a resistor are attached to a cart by an insulating rod. The cart is initially moving to the right along a track with negligible friction at constant speed vo. There is a region of uniform magnetic field with magnitude Bo perpendicular to the plane of the loop and directed into the page as shown above. Current flowing through the loop of wire generates a region of magnetic field Bloop within the wire loop. Which of the following statements describes the changes, if any, in Bloop from the instant the center of the cart is over point A until the instant the center of the cart is over point C ? 4 Bloop is initially zero when the center of the cart is over position A. Bloop increases until the center of the cart is over position C Bloop is initially directed out of the page when the center of the cart is over position A, is zero when it is over position B, and is directed into the page when the center of the cart is over position C. Bloop is initially directed into the page when the center of the cart is over position A, is zero when it is over position B, and is directed out of the page when the center of the cart is over position C. The magnitude of Boop does not change as the center of the cart moves from position A to position C