This is anti-supported because even if the recent observations were accurate, those observations failed to confirm earlier observations about a comet reservoir in the solar system.

This is anti-supported because the recent observations were taken when weather conditions were poor, meaning they are probably not useful results. This means they shouldn’t be used to confirm any findings one way or another.

This is strongly supported because the author states that the recent observations were taken when weather conditions were poor, which casts doubt on their validity. Since Professor Burns uses these observations to cast doubt on earlier observations, Professor Burns is incorrect.

This is unsupported because the author doesn’t explore how we should have interpreted the results of recent observations if those observations had been made under good conditions.

This is unsupported because while the poor conditions cast doubt on recent observations’ usefulness in evaluating the earlier observations, it is too strong to say that the poor conditions makes them entirely worthless.