10. Event A occurs before event B according to you. Both occurred on the x-axis of your reference frame. A was at x = +200 m and B at x = +1000 m. Which observer

(there might be more than one, or none) could possibly claim that B occurs before A:

(a) one moving relative to you in the negative x-direction,

(b) one moving relative to you in the positive x-direction,

(c) one moving relative to you in the positive y-direction, or

(d) none of these could claim that B happened before A?