Question: Searle x Waldron, who won the company formerly known as BHP Steel's Award for Steel Architecture, is based out of what Melbourne city?

Context paragraphs:
BHP: BHP, the trading entity of BHP Billiton Limited and BHP Billiton plc and formerly known as BHP Billiton, is an Anglo-Australian multinational mining, metals and petroleum dual-listed public company headquartered in Melbourne, Victoria, Australia.  Founded in 1885 in the isolated mining town of Broken Hill, it was the world's largest mining company measured by 2015 market values and Australia's fourth-largest company (by revenue), formerly the largest.

BlueScope: BlueScope is a flat product steel producer with operations in Australia, New Zealand, Pacific Islands, North America, and Asia.  It was demerged from BHP Billiton on 22 July 2002 as BHP Steel and renamed BlueScope Steel on 17 November 2003.

Melbourne City Ballet: Melbourne City Ballet is a classical ballet performance company based in Melbourne, Australia.  The company was founded in 2013 by current artistic director Michael Pappalardo and has experienced significant growth in recent years.  Originally created as a neoclassical/contemporary project based company, Melbourne City Ballet has developed quickly over the past few years to become a full-time operating arts organisation with an increasing focus bring classical ballet works to regional and remote communities across Australia.  Melbourne City Ballet is a registered charity with the Australian Charity & Not for Profit Commission under the name MCB Incorporated and is overseen by a board of professionals.

M&amp;M Food Market: M&M Food Market (French: "Les aliments M&M" ), formerly known as M&M Meat Shops, is a Canadian frozen food retail chain.  The company is headquartered in Kitchener, Ontario, and has locations in all ten provinces, the Yukon and Northwest Territories; the company formerly had operations in the Midwestern United States under the MyMenu brand that operated between 2008 and 2013.

Searle x Waldron: Searle X Waldron is an Australian architecture firm based in St Kilda, Melbourne.  It is an emerging firm co-founded by Nick Searle and Suzannah Waldron in 2007.  The firm focuses on projects ranging from small scale residential to larger scale urban master-planning.  Some of their notable projects and design competitions include the MoCAPE (Museum of Contemporary Art & Planning Exhibition) and Art Gallery of Ballarat Annexe which have managed to attain various awards from the Australian Institute of Architects, including the 2012 Colorbond Award for Steel Architecture and 2012 Architecture Award for Public Architecture Alteration & Additions.  Their designs have been exhibited across Australia and throughout Asia and Europe.

Melbourne City FC (W-League): Melbourne City FC, also known as the Melbourne City Women, represents Melbourne City in the W-League, the top division women's football (soccer) league in Australia.  Founded in 2015, the club has its training and administration based at the City Football Academy in Melbourne and plays home games at both the CB Smith Reserve in the northern suburb of Fawkner and at AAMI Park near the Melbourne city centre.  The head coach of the team is player Jess Fishlock.

140 William Street: 140 William Street (formerly BHP House) is a 41-storey steel, concrete and glass building located in the eastern side of the central business district of Melbourne, Victoria, Australia.  Constructed between 1969 and 1972, BHP House was designed by the architectural practice Yuncken Freeman alongside engineers Irwin Johnson and Partners, with heavy influence of contemporary skyscrapers in Chicago, Illinois.  The local architects sought technical advice from Fazlur Khan of renowned American architectural firm Skidmore, Owings & Merrill (SOM), spending 10 weeks at their Chicago office in 1968.  At the time, BHP House was known to be the tallest steel framed building and the first office building in Australia to use a “total energy concept” – the generation of its own electricity using BHP natural gas.  The name BHP House came from the building being the national headquarters of the Broken Hill Proprietary (BHP) Company.  Since being erected, BHP House has been included in the Victorian Heritage Register (Number H1699) for significance to the State of Victoria for following three reasons:

Black Diamond Equipment: Black Diamond Equipment is a manufacturer of equipment for climbing, skiing and mountain sports, based in Utah, USA.  The company also has global offices in Reinach BL, Switzerland and Zhuhai, China.  The company is owned by Black Diamond, Inc., a parent company formerly known as Clarus Corporation, which also owns Pieps and owned POC Sports.

The Muster Point: The Muster Point is a monumental public sculpture in Newcastle, Australia that commemorates the Newcastle Steelworks of the Broken Hill Proprietary Company Limited (BHP) and its workers.  The plant closed after 84 years in operation.  One former worker estimated that "from 1915 to 1961 over 67,000 people had worked on the site".  It was fabricated of steel and bronze by sculptor Julie Squires and BHP workers in the Fabrication Shop before the plant closed down.  The seventy tonne monument is eight metres high, sixteen metres long and twelve metres wide, and demonstrates the significance of steel making to the city of Newcastle.  It was installed on Industrial Drive, in the suburb of Mayfield in 1999.

Eterna: Eterna is a Swiss luxury watch company founded in Grenchen, Canton Solothurn on 7 November 1856 by Josef Girard and Urs Schild.  The company is now owned by Hong Kong based Citychamp Watch & Jewellery Group Limited (an investment holding company formerly known as China Haidian Holdings until 2014).

Supporting paragraphs: Searle x Waldron BlueScope
Answer: St Kilda