This strengthens the manager’s argument. It gives us a reason for why the company should save the product, instead of just abandoning it: because it has invested heavily in this product, and giving it up would harm profits. By filling one of the gaps in the argument--the assumption that the company should try to save the product in the first place--this answer choice makes the argument stronger.

This answer choice repeats something the drug company manager has already stated: that a new marketing campaigns doesn’t guarantee success. We're trying to strengthen the argument that because a new marketing campaign offers a \"one chance\" at saving the product, it should be tried. This answer choice doesn't help us do that.

This doesn't apply to the situation described in the stimulus. This answer choice starts with a sufficient condition--\"if the campaign has no chance to succeed\"--that is already ruled out by the stimulus, which tells us that the marketing campaign does stand at least some chance of success. So this answer choice is irrelevant.

This gives us a reason why the company should not try a new marketing campaign for this product. If they were to start such a campaign, their overall position would be endangered. It seems likely that this damage to the \"overall\" position would be greater than the losses incurred by one product not selling or being abandoned, so it seems less likely that the company \"should\" try a new campaign. Granted, we aren't told for sure how the overall damage from trying a new campaign compares to the potential losses from this product, but we also can't assume that it would be smaller. It's important to see that even if additional information might change our understanding, on its own this answer choice does give us a reason to doubt the conclusion of the argument, and thus weakens it.

This doesn't weaken the argument. If anything, by suggesting that the company might be in a good financial position to take a risk on this new product, this answer choice might weakly strengthen the argument.