Question: What was this major international multi-sport event, with the opening ceremonies taking place on 27 July, and in which the South African field hockey player Bernadette Coston competed for the outh Africa women's national field hockey team?
Sentence (from "Bernadette Coston"): At the 2012 Summer Olympics she competed with the South Africa women's national field hockey team in the women's tournament.
Relevant evidence: Yes