The correct choice for inference questions should be strongly supported by what is stated in the passage.
Look for an answer choice that satisfies one or more of the following:
a) agrees with what is stated in the passage in the line reference
b) agrees with the context or purpose of the paragraph in the line reference
c) agrees with the main idea or purpose of the passage
d) agrees with the tone of the passage
Often, the correct choice is almost a paraphrase of what the author has stated.
Finally, do not stray too far what is stated in the passage when you try to make an inference. The closer the choice is to what is stated in the passage, the more defensible that choice is.
-Good answer choices are defensible using the text of the passage.
-Bad answer choices are not defensible using the text of the passage.