The above options listed the 4 most commonly used 1st languages in South Africa, but which is the most common?

According to the 2011 census the following percentages of people use each as a 1st language:

isiZulu 22.7%

IsiXhosa 16%

Afrikaans 13.5%

English 9.6%

English is widely understood in urban areas of South Africa, despite it being the 1st language of only 9.6% of the population. The majority of South Africans speak 2 or more of the official languages.

More Info: en.wikipedia.org