The correct answer is option 3, Sudan. A peace accord was signed recently in Sudan to end a two-decade old civil war. This peace agreement is particularly significant as it marks a turning point in the country`s history.

Option 1, Colombia, is not the correct answer because although Colombia did sign a peace accord to end a civil war in 2016, it was not recently.

Option 2, Israel, is not the correct answer as Israel has not recently signed a peace accord to end a two-decade old civil war.

Option 4, Haiti, is not the correct answer as there is no recent peace accord signed in Haiti to end a two-decade old civil war.

In summary, the recent peace accord to end a two-decade old civil war was signed in Sudan, making option 3 the correct answer.