tough choice. I think its B and D but I'm going w/ D the most. because if u lean you could lean to much and hit any thing that's next to u. A cant be because then u can't pedal or hardly move it plus it will wobble. C can't be ether because more likely u could customize it to where ur going to really hurt your self but u could costom it to be safer. But I'm going w/ D. I ride my bike a lot in the summer and I'm not that safe on it but I do know how to be safe. the best bet is wearing safety gears.
