The vision test for obtaining a driver's license should not be limited to measuring the adequacy of vision in daylight conditions, as is the current practice. Many people whose daylight vision is adequate have night vision that is inadequate for safe night driving. Most car accidents occur at night, and inadequate vision plays a role in 80 percent of these accidents.
The main point of the argument is thatThe answer to Main Point question must not only be a conclusion supported by the statements in the passage but also capture the main point of the entire passage.
The main point of the entire passage is the final conclusion, which is the conclusion toward which the statements in the passage as a whole are directed.
(A) the vision test for obtaining a driver's license should measure the adequacy of vision in night conditionsThis choice states the main point of the passage.
After all, the passage presents the following evidence:
Many people whose daylight vision is adequate have night vision that is inadequate for safe night driving.and
Most car accidents occur at night, and inadequate vision plays a role in 80 percent of these accidents.That evidence supports the conclusion stated by the first sentence of the passage:
The vision test for obtaining a driver's license should not be limited to measuring the adequacy of vision in daylight conditions, as is the current practice. Then, this answer choice states the main point that follows from all of that.
After all, if it's true that "The vision test ... should not be limited to measuring the adequacy of vision in daylight conditions," then it follows that "the vision test ... should measure the adequacy of vision in night conditions."
It's key to understand that, even though this answer choice to an extent is a restatement of the first sentence of the passage, it's correct. The correct answer to a Main Point question often is just a restatement of the main conclusion in the passage.
Keep
(B) inadequate vision does not play a role in most of the accidents that occur in daylightThe passage does not provide information on what does or does not play a role in accidents that occur in daylight.
Eliminate.
(C) most drivers who have adequate vision in daylight conditions also have adequate vision in night conditionsThe passage does not provide information on the vision of "most drivers."
Rather, the information provided is restricted to the topics of vision testing and when most accidents occur.
Eliminate.
(D) inadequate vision is the primary factor in the majority of car accidents that occur at nightThis choice could seem correct because the passage says, "inadequate vision plays a role in 80 percent of these accidents" that occur at night.
At the same time, this choice is incorrect for two reasons.
One is that the fact that inadequate vision plays a role in 80 percent of nighttime accidents does not mean that inadequate vision is "the primary factor" in the majority of those accidents. It means only that it is a common factor.
Also, even if inadequate vision were the primary factor, that it is would not be the main point of the passage. The main point, which is the point supported by the other statements in the passage, is basically that "The vision test for obtaining a driver's license should not be limited to measuring the adequacy of vision in daylight conditions."
Eliminate.
(E) the current vision test for obtaining a driver's license ensures that most licensed drivers have adequate vision for night drivingThis choice is clearly incorrect because it's contrary to what the passage indicates, which is that "the current practice" is that the vision test is "limited to measuring the adequacy of vision in daylight conditions," which indicates that it does not ensure that drivers have adequate vision for night driving.
Eliminate.
Correct answer: A