White African

I live in South Africa, on the very tip of the African Continent. Am I African? Whenever I have to fill in a form stating my skin colour, I find the following options:

African
Coloured (ie. mixed heritage)
Indian
White

The implication is clearly that black = African whilst the rest of us (Coloureds, Indians and Whites) are second-class strangers on this continent.

Are we not all Africans?