Self-study
Astronaut: Support Any moon, by definition, orbits some planet in a solar system. ███ ███ █████ ██ █████ ██████ ██ ███ █████ ███ ██████ ██████
Summary
The moons of S4 all orbit the planet Alpha. This is because all moons orbit a planet in their solar system.
Missing Connection
What if there were other planets (like Beta and Gamma) in S4 besides Alpha? The moons could orbit those planets instead. Consequently, the astronaut must assume that Alpha is the only planet in S4 to guarantee his conclusion.
5.
The astronaut's conclusion follows logically ██ █████ ███ ██ ███ █████████ ██ ████████
a
There is only ███ ████ ██ ███
The conclusion is about which planet the moon(s) orbit; the amount of moons is irrelevant.
b
Every moon in ██ ██████ ███ ████ ███████
What if all the moons are orbiting a different planet, like Beta, rather than Alpha? The astronaut needs an assumption that guarantees Alpha is the orbited planet.
c
Alpha is the ████ ██████ ██ ███
All moons must orbit a planet in their solar system. So, if Alpha is the only planet in S4, all moons in S4 must orbit Alpha. Therefore, (C) guarantees the astronaut’s conclusion.
d
Every planet in ██ ██ ███████ ██ ████ ████ ███ █████
This leaves open the possibility that moons orbit other planets in S4, which would contradict the astronaut’s conclusion.
e
There is at █████ ███ ████ ████ ██████ ██████
This leaves open the possibility that moons orbit other planets in S4, which would contradict the astronaut’s conclusion.