1. A choice between two good actions
2. A choice between two bad actions
3. A choice between a good and a bad action
If the two choices are polar opposites, then you are in Situation #3. Logic dictates that it is impossible for two actions to be polar opposites, while having the same moral classification.
The philosopher Aristotle would disagree. He teaches that there can be two opposite actions which are both bad. Here's a chart to illustrate this:
|Opposite Actions||Bad Version of #1||Bad Version of #2|
|Love and Hate||Loving my neighbor's wife, i.e. adultery||Murdering my neighbor's wife|
|Truth and Lies||Truthfully insulting people||Lying to get away with murder|
|Exercise and Laziness||Exercise yourself into a coma||Never exercising ever|
Aristotle concludes that the right thing to do is always in the middle of the two extremes.
"Admonish the sinner" is #3 on the list of spiritual works of mercy.