Which of the following conclusions is/are valid? 1. Though SARS-CoV-2 and HMPV are similar viruses with somewhat different epidemiology, the former became a pandemic because it was novel and people had not been exposed to it in the past. 2. The two viruses have fundamentally different impacts on human populations and should not therefore be dealt with in a similar manner. Select the answer using the code given below.

The passage explicitly states that SARS-CoV-2 and HMPV 'belong to two very different virus families with fundamentally different characteristics and epidemiology' — so they are NOT 'similar viruses with somewhat different epidemiology' as Conclusion 1 claims. Hence Conclusion 1 is invalid. Conclusion 2 follows directly from the passage which notes 'Both viruses cause different severity of symptoms... and the affected population segments do not fully overlap', implying they have fundamentally different impacts and warrant different handling. So only Conclusion 2 is valid.