Creating vivid imagery means painting a scene by appealing to the senses. The sentence about autumn leaves crunching underfoot and the air smelling of rain does exactly that by using sounds and smells to bring the moment to life. “Crunch underfoot” lets you hear the dry, crisp sound of leaves as you walk, while “the air smells of rain” engages the sense of smell and hints at a damp, earthy atmosphere. The combination of these sensory details helps readers picture the scene more vividly. The other sentences focus more on actions or states rather than painting a sensory picture. A line about a character facing a dilemma communicates conflict but not sensory detail. A sentence saying the plot moved quickly describes pace, not imagery. A line about a character speaking softly mentions sound but doesn’t evoke a richer scene with multiple senses.