To see why "conflicts" means cannot be true rather than weaken, consider the following hypothetical passage and answers:
In order to make a delicious cake, one needs to use real sugar. According to chefs, having delicious cake is an important factor in becoming a successful restaurant. Therefore, restaurants should stock plenty of real sugar if they want to be successful.
Which one of the following conflicts with information in the passage?
a. The "honeybun" is a delicious cake that only uses honey as sweetener. b. Chefs are not the best judges of how a restaurant can become successful.
Answer a directly conflicts with a statement in the passage - it is an example of a delicious cake that does not use real sugar. Answer a cannot be true if the information in the passage is correct.
Answer b on the other hand weakens the argument in the passage, as it gives us a reason to doubt whether chefs can provide the linkage between real sugar and restaurant success. But this answer does not directly conflict with any information in the passage - it instead gives us a reason to doubt the chain of argument.
I hope this helps, please let us know if you have further questions.
