Answer: The correct option is (B) 0.8.
Step-by-step explanation: Given that an ellipse has foci at (4, 0) and vertices at (5, 0).
we are to find the eccentricity of the ellipse.
We know that the eccentricity 'e' of an ellipse with foci at (c, 0) and vertices at (a, 0) is given by
In the given ellipse, we have
foci, (c, 0) = (4, 0) ⇒ c = 4,
vertices, (a, 0) = (5, 0) ⇒ a = 5.
Therefore, the eccentricity of the ellipse is

Thus, the correct option is (B) 0.8.