Which action is appropriate to weaken a causal conclusion?

To weaken a causal conclusion, it is effective to find an alternative cause. A causal conclusion typically asserts that one event or condition directly leads to another. By introducing an alternative cause, you provide a different explanation for the observed effect, suggesting that the original cause may not be the only or primary factor involved. This undermines the strength of the causal relationship because it raises the possibility that the effect could be attributed to something else altogether.

For instance, if a study concludes that increasing exercise leads to weight loss, demonstrating that changes in diet also contribute to weight loss weakens the original causal link by suggesting there is another factor at play. This gives reason to doubt the claim that exercise is the sole cause of weight loss.

The other choices do not effectively weaken a causal conclusion in the same manner. Showing that the effect always occurs would actually strengthen the case for a causal link, as it implies a consistent relationship. Proving no relationship exists can be overly strong if we are considering correlations, as it may not adequately address alternative outcomes. Agreeing with the stated cause does not weaken the argument; rather, it supports the original causal claim. Thus, identifying an alternative cause is the most effective way to challenge and weaken a causal assertion.