Complete the sentence with the best relative pronouns respectively: “Albert Sabi...

Questão de Inglês da banca SERCTAM aplicada no concurso Prefeitura de Crato CE (2012). Confira a resolução completa abaixo:

Complete the sentence with the best relative pronouns respectively:

“Albert Sabin, ____ has never won a Nobel Prize, invented an oral vaccine ____ prevents the poliomyelitis.”