negative rules in answers signal wrong answers because they give us nothing that can explain what rule applies to the premises and conclusion to make the reasoning justified.

This type of question is really important to capture flaws in our reasoning. I see that in the comments there is debate about A being right because it fails to clearly communicate how the lack of intensity of projectiles striking Mars during the LHB period would show no support for hypothesis 2.

But I do think A can be seen as ruling out and failing to support hypothesis 2. This is because the time period mentioned allows us to make the inference that we would see an increase in intensity of projectiles striking Mars during the period '3-4' billion year period, while seeing a decline in the '4-5' billion year period. However, if as A says there is a lack of evidence for the increase in intensity during the 3-5 billion years, either before or after the conclusion as hypothesis 2 would suggest, then hypothesis 2 is not supported at least for one inner solar system planet—Mars.

Hi Kevin!