Which situation might keep an embargo against a country from being successful? The country is able to find other trading partners
The country does not need to trade with the other countries
People in the other country suffer because trading has stopped
People in the other country don't care whether their country trades with other countries

The country is able to find other trading partners.

Explanation:

In an Embargo, a country tried to hurt the economic condition of other country by blocking all form of trades between them. Often times, that country influence its other allies to trade with the embargoed country to increase the damage. This process wouldn't be successful if the embargoed country can find another trading partners despite the blockade.

Example of this would this when United States put an embargo to Cuba in 1960 to hurt its economy. The Embargo wasn't really successful because Cuba managed to established new trading relationship with the Soviet Union.