Self-paced
Scientists examined diamonds that were formed on Earth about 2.9 billion years ago. █████ ████████ ███ █ ██████████████████ █████████████ ██ ██████████ ████ █████████████ ███ ██ █████████ ████ ██ ███████ ████████ █████████ ████ ███ ██████████ ██ ███████████ ██████ ██ █████ ███ ████ ████ ████ █ █████ ██ ██████ ██ ███████ ██████████ ███ ███████ █████ ████ ████ ███ ██████ ███████████ █████ █████ ████ ███████ ███████ ███████ ██ █████████ ███ ████████ ██████████
Summary
Diamonds formed 2.9 billion years ago have an unusually high concentration of sulfur-33. This can only be caused by a chemical reaction triggered by ultraviolet light. If there was more than a trace of oxygen in the atmosphere 2.9 billion years ago, then not enough ultraviolet light would be present to cause the chemical reaction.
Strongly Supported Conclusions
2.9 billion years ago, the atmosphere contained at most a trace amount of oxygen.
11.
The information above most strongly ████████ █████ ███ ██ ███ ██████████
a
Most diamonds with ██████████████████ ██████████████ ██ █████████ ████ ██████ ██ █████ ███ ███████ █████ ████
This answer is unsupported. We only know from the stimulus that there some of these diamonds were formed 2.9 billion years ago. We have no idea how many of these diamonds exist in total, or when they were formed
b
Ultraviolet light causes ███ ██████ ██ ███████ ██████████ ██ █████ ██████████ ████ ██████████
This answer is unsupported. We don’t know whether the oxygen specifically reacted with sulfur-33. We only know from the stimulus that a “certain chemical reaction” occurs when stimulated by ultraviolet light.
c
Earth's atmosphere contained ████ ███████ ██ ████ ██████ ███ ███████ █████ ████
This answer is strongly supported. The diamonds' high concentration of sulfur-33 is only possible if UV light stimulated a reaction, and that is only possible if the atmosphere had very little oxygen.
d
Sulfur-33 is rarely █████ ██ ████████ ████ ████ ██████ ████ ████████ ████ ███ ███████ █████ ████
This answer is unsupported. We don’t know anything about more recently formed diamonds from the stimulus. The stimulus is strictly limited to the diamonds from 2.9 billion years ago.
e
The formation of ████████ ██████ ████ ██ ███ ████████ ██ ███████████ ██████
This answer is unsupported. We don’t know from the stimulus under what conditions diamonds are formed generally.