Self-study
Prominent government officials have denied that their policies have produced serious environmental degradation. ███ ███ █████ ████ ██████████ ████ █████ ██ ███ ██████ ██ ███████ ██████ ██████████ ███ ██████████ ████████ █ █████████████ █████████ ███████████ ███ ███████ ██ ██████ ██████ ████ ████████ █████ ████ █████ ████████ ██ █████ ██ █████ ███████ ████ ████ ██████ █████ █████████ ██████ ███████
Summarize Argument: Phenomenon-Hypothesis
The author hypothesizes that government policies have led to serious environmental degradation, despite government officials' claims to the contrary. This hypothesis refers to the large amount of mining waste that has been dumped into "vital" streams since the government lifted a ban on such dumping. So for the author, because this policy change was followed by a significant amount of environmentally-damaging dumping, the policy change is taken to have caused the dumping.
Necessary Assumptions
We're looking for an assumption on which the argument relies—in other words, a necessary assumption. The author has identified an environmental harm, as well as a government policy that seems related to that harm. However, the author hasn't established the conclusion that the government policy is actually the cause of the harm. That means it's necessary for the author to make an assumption about causality.
So, what we're looking for is an answer that fills in the missing piece of causality. The necessary assumption will tell us that the government policy is the true cause of the dumping, and that the mining companies weren't just carrying out the same practice illegally while the ban was in force.
6.
The argument relies on which ███ ██ ███ █████████ ████████████
a
Without the urging ██ ███████ ██████ ██████████ ███ ██████████ █████ ███ ████ ██████ ███ ███ ██ ███████ ██████ ██████ ████ ████████
The assumption the author makes is about what caused the mining companies to dump waste into streams, not about what caused the policy shift. An assumption about why the government lifted the ban isn't necessary to an argument about the effects of doing so.
b
The prominent government █████████ ███ ████ ████ ██████████ ████████ ████ ████████ ███████ █████████████ ███████████ ██ ███ ██████ ███████ ████ ████ ███ █████████
Whether or not the government officials believe in their claims makes no difference to the argument. The argument is about the effect the government's policies have had on the environment, and this assumption isn't necessary for that.
c
The mining companies ████ █████ ██████ ██ ███ ███ ██ ███████ ██████ ██████ ██ ███████ ████ █████ █████ ████ ██████ ████████ ██ █████ ██ ███████ █████ ██████ ███████
The author is trying to establish that lifting the ban caused an increase in dumping mining waste in streams. That conclusion is unaffected by which exact companies engaged in lobbying or dumping, meaning this assumption isn't necessary.
d
The government is █████████ ████ ██████████ ██ █████████ ████ ███ ██████ ████████ ████ ████ ██████████████████
Like (A), the reasons behind the policy change are immaterial to the actual effect the policy change has had. This argument doesn't rely on any assumptions about which lobby groups the government pays attention to.
e
If the ban ██ ███████ ██████ ██████ ██ ███████ ███ ███ ████ █████████ ████████████ ████ ██████ █████ █████ ████ █████ ███ ███ ████ ████████
In other words, lifting the ban actually caused an increase in dumping. If we didn't make this assumption, the argument would fall apart—if the mining companies were dumping waste anyway, then repealing the ban couldn't be said to make a difference. That's what makes this a necessary assumption.