Which most likely explains why some countries lack opposition parties? they lack popular support. they destroy the election process. they oppose the interests of the people. they are prohibited by law.

Some countries lack opposition parties because they are prohibited by law. The last option is correct.

Countries which lack political parties include:

Bahrain – Political "parties" are banned, but political "societies" are allowed. The media, however, usually refer to these formations as "parties".

Oman – Political parties are banned.

Kuwait – Political "parties" are not legally recognized, but political blocs are allowed. The media, however, usually refer to these blocs as "parties".

Qatar – Political parties are banned.

Saudi Arabia – Political parties are banned.[1][2]

United Arab Emirates – Political parties are banned.

 Vatican City State

Tuvalu

Brunei