Ok you can use POE

1. The passage does not mention anything about the fact that Paczynski's theory is no longer credited. Out of Scope

2. Again there is no criticism mentioned against Paczynski or any other astronomers theory. Out of Scope.

3. The author does discuss the reason why Pacynski proposed the MACHO theory, but the passage does not discuss whether the theory was influential or whether any one got influenced by it. The 2nd part is Out of Scope.

4. No dispute between the astronomers is mentioned. Irrelevant.

5. The author first explains Paczynski's theory. Then he says that the microlensing logic can be flawed and he goes on to explain why it could be incorrect. Notice this line in the passage, 'can be mistaken for microlensing'. The portion after this line, the author explains why the astronomers can mistaken the phenomenon as microlensing. (Its in the 10th last line).

Thanks for the response ... thats useful to understand why the incorrect answer choices are wrong.