Neither, because both are very talented girls and I'd like to see both succeed.
And no, I don't think Cain has been ducking Efraimson so far this outdoor season. My opinion will change if Cain actually runs the 3000m instead of the 1500m at Junior Nationals, but I'll surprised if that happens.
Cain declared for the 3000, but for some reason did not qualify (probably because her time is too old in that event). So unless Salazar bribes the officials we will get to see them finally race at 1500m!