The correct answer is letter D. An example of a metaphor is “His mind was a steel trap.” This answer is due to the fact that Merriam-Webster dictionary defines metaphor as “a figure of speech in which a word or phrase literally denoting one kind of object or idea is used in place of another to suggest a likeness or analogy between them…”
The word metaphor is derived from the Old French word metaphore and the Latin word metaphora which mean to carry over, to transfer or to carry meaning. I.A. Richards described metaphor in his book entitled The Philosophy of Rhetoric as having two different parts – the tenor which is the subject and the vehicle which is the object.