[vhcook]

Barring any actual knowledge of opponent abilities, this is how I'd go:

A: Cheval de Frise - doesn't block vision as much as the drawbridge, requires precision driving
B: Ramparts - likely to flip a robot that attempts a "Dukes of Hazzard"-style crossing
C: Sally Port - harder to open from outside as it requires compound movement, blocks vision less
D: Rock Wall - I remember how few robots could clear the barrier back in Rebound Rumble.