Many workers who handled substance T in factories became seriously ill years later. We now know T caused at least some of their illnesses. Earlier ignorance of this connection does not absolve T's manufacturer of all responsibility. For had it investigated the safety of it, many of their illnesses would have been prevented.
What this question is testing
Your task
Break the argument into its conclusion and evidence, then do exactly what the question stem asks with that structure.
Common trap
Answers that sound relevant to the topic but don't connect to the argument's actual reasoning.
Winning move
Predict what a right answer must do, then test each choice against the conclusion-evidence gap.
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