6. Given that are the common foci of an ellipse and a hyperbola, and is one of their common points, with , then the minimum value of the product of the eccentricities of the ellipse and the hyperbola is
A、
B、
C、 1
D、
Problem 627
6. Given that are the common foci of an ellipse and a hyperbola, and is one of their common points, with , then the minimum value of the product of the eccentricities of the ellipse and the hyperbola is
A、
B、
C、 1
D、