Question: what language is spoken in south america by the inca descendents?
Answer: Quechua was spoken by some of these people, for example, the Wanka, before the Incas of Cusco, while other people, especially in Bolivia but also in Ecuador, adopted Quechua only in Inca times or afterward. Quechua became Peru's second official language in 1969 under the infamous dictatorship of Juan Velasco Alvarado.