Question: Which city's southern suburbs were the location of an electoral district which lost Labor-voting areas to Victoria Park, Canning and Welshpool, and became substantially safer for the major political party in Australia founded in 1945?
Sentence (from "Matara Electoral District (1947–1989)"): The existing 160 mainly single-member electoral districts were replaced with 22 multi-member electoral districts. Matara electoral district was replaced by the Matara multi-member electoral district at the 1989 general elections, the first under the proportional representation system, Matara continues to be a polling division of the multi-member electoral district.
Relevant evidence: No