Self-study
Astronomer: Support Earth was bombarded repeatedly by comets and asteroids early in its history. ████ ███████████ ████████ ██████████ ███ ███████ ███ █████████ ████ ████ ███████████ ██████ ████ █████ ██████ ██ ███████ ██████████ ████████ ██████████ ████ ███████ ██████ ████████████ ███ ██ █████ █████ ████ ████ █████████ ████ ██ ████ █████ ██ █████ █████ ████ ████ ██ ██████ ███████ ████ ██████████ ███████████ ████ ████ ████ ██████ ██ ██████ ████ ██ █████ ███ ████ ███████ ████ ██████ ████████ ████ ███████ ████ ████ ████ ██ █ ██████████
Summarize Argument
The astronomer concludes that life on Earth might have started with a microbe-carrying meteorite from Mars. Why should we believe this? Because although Earth was probably rendered inhospitable to early life by asteroid strikes, Mars escaped such strikes and therefore could have fostered life early in its history. And, we know that many meteorites originating on Mars have ended up striking Earth.
Identify Argument Part
The referenced text helps support the claim that life on Earth might have started with a meteorite from Mars. If Mars actually wasn’t able to generate microbial life before Earth was, then there would be no reason to believe the meteorite argument. So, the author asserts in the referenced text that Mars could have hosted microbial life before Earth did. In addition, it's important to note that the referenced text receives support of its own; the author points out that Mars escaped severe asteroid bombardment as support for why there could have been microbial life on Mars before there was such life on Earth.
20.
Which one of the following ████ ██████████ █████████ ███ ████ ██████ ██ ███ ████████████ ████████ ██ ███ █████████ ████ █████ █████ ████ ████ █████████ ████ ██ ████ █████ ██ █████ █████ ████ ████ ██ ██████
a
It is a █████ ███ █████ ██ █████████████ ██ ████████ ███ ████ ██ ████████ ██ █████ ██ █████████ ███ ██████████ ████ ███████████
The referenced text receives justification (support) from the claim that Mars escaped asteroid bombardment early in its history.
b
It is a █████ ███ █████ ██ █████████████ ██ ████████ ███ █████ ██ █████ ███████ ███ █████ ██ ███ ██████████ ████ ███████████
The referenced text receives justification (support) from the claim that Mars escaped asteroid bombardment early in its history. Also, the referenced text doesn’t **ensure** the truth of the argument’s main conclusion, because there might be other factors that make the author's main conclusion implausible or even false. Even if Mars could have had microbial life before Earth, that does not guarantee that Earth's life may have started from meteorites from Mars.
c
It is a █████ ███ █████ ████ █████████████ ██ ████████ ███ ████ ██ ████████ ██ █████ ██ █████████ ███ ██████████ ████ ███████████
The referenced text receives justification (support) from the claim that Mars escaped asteroid bombardment early in its history. It’s also required to establish the conclusion. If Mars could not have had microbial life before Earth had such life, then the theory that Earth's life may have started from meteorites from Mars would be impossible.
d
It is a █████ ███ █████ █████████████ ██ ████████ ███ █████ ██ █████ ███████████ ███ █████ ██ ███ ██████████ ████ ███████████
The referenced text isn't sufficient to establish the truth of the argument’s main conclusion, because there might be other factors that make the author's main conclusion implausible or even false. Even if Mars could have had microbial life before Earth, that does not guarantee that Earth's life may have started from meteorites from Mars.
e
It is a █████ ████ ████████ ████ ███████ ███ ███ ██████████ ██████████ ███ ████ ███████ ███████ ███ █████ ██ ████ ██████████ ███ ██ ████████ ██ █████ ██ █████████ ████ ███████████
The referenced text **is** required to establish the main conclusion. If Mars could not have had microbial life before Earth had such life, then the theory that Earth's life may have started from meteorites from Mars would be impossible. So the author's theory does require Mars to have had microbial life before Earth had such life.