Answer:
"dark, forlorn" (line 4) separated on a line by itself to emphasize the contrast between the characteristics of the waterdrop and the thorn, Option B.
Explanation:
The given lines are from the poem "Remembrance" by Walter De la Mare.
He writes dark, forlorn in a separate line to show the difference in characteristics of water drop and thorn. Water drop is defined as clear and beautiful. On the other hand, thorn is always painful. So, he defines it as dark and forlorn. Forlorn means sad or hopeless. So, Option B clearly defines the motive oft he author here.
He is not trying to give visual aspect or a break in the lines of his poems as given in other Options.
