The correct answer is option- 2, Mauritania. This country does not border with the Mediterranean Sea. To understand why, let`s look at the other options.

Option- 1, Algeria, does border with the Mediterranean Sea. Algeria is located in North Africa and has a coastline along the Mediterranean Sea.

Option- 3, Morocco, also borders with the Mediterranean Sea. Morocco is located in the western part of North Africa and has a coastal strip along the Mediterranean Sea.

Option- 4, Tunisia, is another country that borders with the Mediterranean Sea. It is located in the northeastern part of Africa and has a coastline along the Mediterranean Sea.

However, option- 2, Mauritania, is the only country among the options that does not have a coastline along the Mediterranean Sea. Mauritania is located in the western part of North Africa and is bordered by the Atlantic Ocean to the west.

Therefore, the correct answer is option- 2, Mauritania, as it does not border with the Mediterranean Sea.