Attachment 68393

Trying to work out how to do this. I know the answer is B but don’t know how.

Internal resistance is negligible so I assume I just use I =V/R. I’ve tried using sample values for R eg 5 and V =10V giving I as 1.3 but am no closer to 2/3. What am I missing?

http://ift.tt/1kiXm5l