To answer "main idea" questions you do not have to read the whole passage. You can look at the start and the end of each paragraph if you are running out of time, soMost farmers attempting to control slugs and snails turn to baited slug poison, or molluscicide, which usually consists of a bran pellet containing either methiocarb or metaldehyde. (...) Moreover, slugs are not the only consumers of these poisons: methiocarb may be toxic to a variety of species, including varieties of worms, carabid beetles, and fish.
Researchers are experimenting with an alternative compound based on aluminum, which may solve these problems, but this may well have a limited future as we learn more about the hazards of aluminum in the environment. (...) With farmers losing as much as 20 percent of their crops to slugs and snails even after treatment with currently available molluscicides, there is considerable incentive for researchers to come up with better and environmentally safer solutions.
The first paragraph says: Farmers use slug poison agaist slugs and snails, but there are some drawbacks because other animals eat it.
The second paragraph says: The is new research going on. Maybe aluminum could not be a solution, but there is considerable incentive for researchers to come up with better and environmentally safer solutions.In the passage, the author is primarily concerned withA: describing the limitation of molluscicides that affect feeding behavior
Maybe, but this refers to the 1st paragraph alone, so is incorrect.B: proposing alternatives to current methods of controlling slugs and snails
The author does not propose anything, "I suggest this" or "my method is" are not present in the passage.C: emphasizing the need for an alternative to currently available molluscicides
This is correct. The first paragraph says that the current method does not work properly, the second ends with this sentencethere is considerable incentive for researchers to come up with better and environmentally safer solutions.
You should keep an eye on the last sentence of the text, because it could summarize the whole point or give you a clue for this questions.D: explaining how molluscicides are used to control slugs and snails
The author does not explain how molluscicides is used. You do not find in the text anything like an explanation of its usage (like: place it near a given point, and so on...)E: criticizing the use of hazardous material for controlling slugs and snails
Maybe, but this refers to the 2nd paragraph alone, so is incorrect.The author suggests that which of following is true of the "alternative compound" mentioned in the highlighted text?
Go back to the text:Researchers are experimenting with an alternative compound based on aluminum, which may solve these problems, but this may well have a limited future as we learn more about the hazards of aluminum in the environment.
So the alternative compound solves some problems BUT is not enviornmentally safe.A: It is more effective in destroying snails than in destroying slugs.B: It begins to affect snugs' feeding behavior before they ingest a lethal dose.C: It affects more species of fish than does metaldehyde.D: It may not be enviornmentally safer than methiocarb.
CORRECTE: It may be less damaging to trees than metaldehyde.The author cites which of the following as a disadvantage of methiocarb?
Scan the passage and look for the word "methiocarb ":methiocarb may be toxic to a variety of species, including varieties of worms, carabid beetles, and fish.A: It contains high levels of aluminum.B: It may react with acid rain to kill tres.C: It has been associated with Alzheimer's disease.D: It may be toxic to some species of fish.
CORRECTE: It may not be as effective in killing slugs as metaldehyde is.
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