Which of the following lenses would you prefer to use while reading small…

To read small letters in a dictionary, a convex lens with a short focal length is required to act as a magnifying glass. Option A has a 50 cm convex lens, which is too long for effective magnification. Options B and C are concave lenses, which diverge light and cannot magnify text. Option D suggests more than one correct choice, but only a short focal length convex lens would work. Since none of the options provide such a lens, 'None of the above' is correct.