If Hershey and Chase had found 'S in both the pellet and the supernatant, the conclusion about the nature of DNA replication would be that:
(a) Protein must be the information molecule
(b) It would be difficult to conclude anything from these results
(c) DNA is the genetic information molecule
(d) Phage must have stuck to the bacteria
The information provided in the question is incomplete as we cannot infer anything from presence of Sulphur in pellet and supernatant.
If it would have been Phosphorus, then we could say that genetic material has transferred.