The Sharpeville Massacre of 1960 was a turning point in the struggle against apartheid because it led to

The massacre actually led to worldwide condemnation of apartheid. Countries around the world saw the violence and opposed South Africa. This increased international support for anti-apartheid movements, not for apartheid itself.

The ANC and PAC were banned after the massacre. But this wasn’t increased support for apartheid. Apartheid didn’t end immediately, lasting until 1994. South Africa was already independent since 1910.

Note: The marked answer appears incorrect based on historical facts. The massacre increased opposition to apartheid globally, not support for it.