. . . . . . . . shortest man in . . . . . . . . world and . . . . . . . . tallest man in . . . . . . . . world live in . . . . . . . . Africa.

In the first blank, article "the" will be used because article 'the' is used with superlatives (shortest).
In the second and fourth blank, article "the" will be used because 'world' is a proper noun. There is only one 'world'.
In the third blank, article "the" will be used because "tallest" is superlative and article 'the' is used with superlatives.
In the fifth blank, no article or 'zero article' will be used because 'Africa' is a country and no article is used before a country name.