This task is about writing a correct answer for the reading comprehension task. Based on the information provided in a given passage, you should identify the shortest continuous text span from the passage that serves as an answer to the given question. Avoid answers that are incorrect or provides incomplete justification for the question.

Passage: Melbourne has the largest Greek-speaking population outside of Europe, a population comparable to some larger Greek cities like Larissa and Volos. Thessaloniki is Melbourne's Greek sister city. The Vietnamese surname Nguyen is the second most common in Melbourne's phone book after Smith. The city also features substantial Indian, Sri Lankan, and Malaysian-born communities, in addition to recent South African and Sudanese influxes. The cultural diversity is reflected in the city's restaurants that serve international cuisines. Question: Which city in Greece is Melbourne's sister city?
Thessaloniki