Answer: A. The phrase "ruthless and utter destruction", because its tone is calm but its message is frightening.
Explanation: In this excerpt from "The War of the Worlds" by H.G. Wells, the feature of the passage that most strongly builds suspense is the phrase "ruthless and utter destruction", because its tone is calm but its message is frightening. This phrase is frightening because the narrator is comparing the destruction the human race has made in the environment with what the aliens did in their invasion of Earth.