you always want to pull with an inline fan like that, so your B option would be the best. This must be a rather powerful fan, because of the distance, the amount of 90 degree bends (what will really lower your fan efficiency), and the fact that your pulling through a carbon filter and then through the hood and then through all the ducting. If its sealed up well enough and powerful enough fan...then it will work fine. Cool tubes will help make sure its entirely sealed.

The best way would involve 2 fans, which often is not feasible. If you could do that, then I would run a sealed cooltube so that air is pulled from outside the grow room, through the light, and then is exhausted back outside the room. This keeps it sealed so no filter is needed for cooling the light. Then use your filter to draw air from the room, exhaust it through the filter, and out the room with another fan. Use a passive intake if the room is sealed enough. This will keep all your exhaust smelling nice, and your light will be as considerably cooler because its drawing colder air from outside the warm room. But its 2 fans.