It can be inferred from the passage that which of the following would most probably be observed during the Earth's passage through a meteor stream if the conventional theories mentioned in line 9 were correct?
In years in which the Earth passed through only the outer areas of a meteor stream, meteor activity would be absent.
The question is to make an inference about what would most probably be observed during the Earth's passage through a meteor stream if the conventional theories mentioned in the passage were correct.
According to line 9-11, the conventional theories predicted that the meteor stream would be most dense at the center. The computer model, on the other hand, predicted that a meteor stream would come to resemble thick-walled, hollow pipe. The passage states that, if the computer model were correct, two peak periods of meteor activity would be observed as the Earth passed through the walls of the "pipe".
According to the passage, observational data confirmed the prediction of the computer model. If, on the other hand, the conventional theories were correct, it can be inferred that a bifurcation of meteor activity would not be observed; instead, it can be inferred that scientists would expect to observe a single peak of meteor activity as the Earth passed through the dense center of the stream.
The option - In years in which the Earth passed through only the outer areas of a meteor stream, meteor activity would be absent - is correct because the passage says that meteor showers occur whenever the Earth passes through a meteor stream; it cannot be inferred that either theory would predict otherwise.