Let `Sa n dS '` be two foci of the ellipse `(x^2)/(a^2)+(y^2)/(b^2)=1` . If a circle described on `S S^(prime)` as diameter intersects the ellipse at real and distinct points, then the eccentricity`e` of the ellipse satisfies (a)`c=1/(sqrt(2))` (b) `e in (1/(sqrt(2)),1)` (c)`e in (0,1/(sqrt(2)))` (d) none of these