He is comparing desire for love with fire which can be destructive and also ice with hate which can be just as destructive if not controlled.
A good explanation that I found about the theme of this poem states: "Frost equates fire with desire, a burning force that originates out of love and is equally destructive as ice, which he presents as similar to hate."(Theme of the poem fire and ice).
The answer to the question above is option D: misunderstanding destroys relationships. Basing on the excerpt taken from "<span>fire and ice" by Robert Frost, this clearly shows how misunderstandings can destroy relationships by any means. Fire and Ice here represents the methods of how one relationship can be destroyed. Either way, may it be fire or ice, both has still the potential to destroy something.</span>
