lets just understand the information that we have
We are specifically talking about the nation Partoria. In Partoria, large trucks(number of the large trucks can be any number) currently account for 6% of the total miles driven on Partorian roads ie the number of miles driven by large trucks on partorian roads is 6% of total number of miles driven by all the vehicles, including cars, buses, etc etc.. (total number of miles driven by all vehicles can be any number)
Large trucks are "involved" in 12% of all highway deaths/fatalities. One thing to note here is that being involved in something doesn't mean causing that something.
The very largest trucks - those with three trailers - had less than a third of the accident rate of a single and double trailer trucks. Important thing to know here is the logical gap, which is the difference between accident rate and fatality rate. Accident rate is basically related to the number of accidents, and fatality rate is related to the number of deaths. So a low accident rate doesn't necessarily mean few fatalities or deaths.
conclusion : typical goal - plan structure ie
plan is : shippers must increase their use of triple trailer trucks
goal : reduce highway deaths
so basically we need to evaluate whether the mentioned plan which is "increasing the usage of triple trailer trucks" will help is achieving the goal, which is "reducing highway deaths".
now lets look at the options -
option A :
does this option help us in answering the question - whether the mentioned plan, which is "increasing the usage of triple trailer trucks", will help is achieving the goal, which is "reducing highway deaths" ? clearly not. Also this option is basically saying no matter what changes in regulation of trucking are made, large trucks, including both greater than or equal to three trailers and less than equal to two trailers, must be kept off small roads, roads that basically are not highways, but are conclusion is about the highways....Irrelevant : no impact
option C :
fatal collisions, collisions in which someone dies, can involve two cars, two buses, one car and one bus, two trucks etc etc..again, ask yourself whether this option helps us in answering the question - whether the mentioned plan which is "increasing the usage of triple trailer trucks" will help is achieving the goal, which is "reducing highway deaths" ? clearly not......Irrelevant : no impact
option D : okay so the safety record has improved slightly over the past 10 years, but that doesn't impact our argument, which is about the current situation in Partoria.... Irrelevant : no impact
option E : we have to understand that this option doesn't necessarily say that the triple trailer trucks are heavier than single trailer trucks. We can have a three trailer truck with each trailer with max payload of 50 kilograms making the over payload to 150 kilograms, and we can have a single trailer with max payload of 200 kilograms. Let us now consider that an average triple trailer truck is heavier than even a largest of a single trailer truck, maybe this is the reason that triple trailers have a lower accident rate than single and double trailers do as the triple trailers are heavier hence they move slower or whatever, but then we are concerned about the fatality rate ie number of deaths on highways. Heaviness can help us in explaining the accident rate, but how does it affect the number deaths, we can't really say...... this option is not relevant to our conclusion
option B : lets say that the partorian trucking companies have in total 100 truck drivers. Logically, best, most experienced will be a small percentage of the those 100 drivers, maybe 5 percent of the 100 drivers are best and most experienced. Obviously the best/most experience cannot be a large percentage of the total number of drivers right? So even if we increase the usage of triple trucks, then that won't help us in achieving our goal unless the number of best and most experienced drivers, which is a very small number, increases. The number of best, most experienced drivers will remain the same (give or take 1 - 2 drivers) even if they hire new drivers. So if the number/usage of triple trucks increases, not best and less experienced drivers will have to take on those new triple trailers and that could lead to a greater number of highway deaths.
PS : Hey experts, If you feel that my explanations are incorrect/incomplete/ not precise, please feel free to comment