please explain why statement is wrong or correct

Which statements are true about lenses in combination? Select all that apply. A} The focal length of a lens combination is always less than the focal lengths of the individual lenses. E} The image ofthe first lens acts as the object for the second IEns. C} Lenses in combination can be described by an effective focal length. D] Lens combinations can be used to correct aberrations. E] The total magnification of a combination of lenses is the sum of their individual magnifications