The correct answer is: D. All of the above
The United Nations declared 2008 as the International Year of Languages, the International Year of the Potato, and the International Year of Sanitation.
The International Year of Languages was celebrated to promote multilingualism and the importance of languages in the world. The International Year of the Potato was celebrated to raise awareness of the importance of potatoes as a food source and to promote sustainable potato production. The International Year of Sanitation was celebrated to raise awareness of the importance of sanitation and to promote access to sanitation for all.
The United Nations has declared many International Years, which are periods of time dedicated to promoting a particular issue or theme. These years can help to raise awareness of the issue, promote action, and encourage cooperation among countries.