The sentence that best explains the different ways in which fact and historical fiction are used in a story is option D. while facts can be proven, historical fiction includes imagined details to add dramatic interest. A historical fiction is described as an imagined story that happens in the past and sometimes adopts a real time period in which the story is set.
The poet compared imagination to a soaring bird because imagination is limitless, it can do anything and go anywhere, much like a soaring bird, who has the freedom and capabilities to do anything. Both are completely free of bounds.