7. As shown in the figure, in isosceles trapezoid $A B C D$, $A B / / C D, A B=2 C D, \angle A=60^{\circ}$, and $E$ is a point on the base $A B$, such that $F E=F B=A C$, $F A=A B$.
Then $A E: E B$ equals
(A) $1: 2$;
(B) $1: 3$;
(C) $2: 5$;
(D) $3: 10$.