I would go with Brown v Board of Education. It gave more rights to African Americans and made them one step closer into beating segregation. Through the court case, segregation in schools was deemed unconstitutional, and so was segregation in other public places.
<span>The united states would have had to keep its commercial vessels out of waters patrolled by U-boats. This would have been politically unpopular and economically damaging.</span>
There is more technology is one way.
OK so basically he didn't have the power to do anything forcefully so he bargained I believe the best choice will be D.