Question

read an excerpt from al gores nobel lecture:
so today, we dumped another 70 million tons of global - warming pollution into the thin shell of atmosphere surrounding our planet, as if it were an open sewer. and tomorrow, we will dump a slightly larger amount, with the cumulative concentrations now trapping more and more heat from the sun.
what type of appeal does gore use to warn about global warming?
a. he uses precise data to convince the audience.
b. he uses an emotional metaphor to persuade his audience.
c. he uses exaggerations to upset the audience.
d. he uses his position as vice president to persuade his audience.

Explanation:

The text uses the metaphor of the atmosphere as an "open sewer" which is an emotional and vivid comparison to persuade the audience about the negative impact of global - warming pollution. The mention of "70 million tons" is not extremely precise (as it's a large - scale, rounded number) and not the main appeal. There's no indication of exaggeration beyond the metaphor, and there's no reference to his position as vice - president in this excerpt.

Answer:

B. He uses an emotional metaphor to persuade his audience.