The 2010 CIA World Factbook

by United States. Central Intelligence Agency

Chad
18 years of age; universal

Chile
18 years of age; universal and compulsory

China
18 years of age; universal

Christmas Island
18 years of age

Cocos (Keeling) Islands
18 years of age

Colombia
18 years of age; universal

Comoros
18 years of age; universal

Congo, Democratic Republic of the 18 years of age; universal and compulsory

Congo, Republic of the
18 years of age; universal

Cook Islands
18 years of age; universal (adult)