Question: In which city are the headquarters of the multinational defence, security and aerospace company, one of the world's largest and ranked 3rd based on revenues in 2015, which has the subsidiary British Aerospace? 
Sentence (from "BAE Systems"): The company was formed on 30 November 1999 by the £7.7 billion merger of two British companies: Marconi Electronic Systems (MES) – the defence electronics and naval shipbuilding subsidiary of the General Electric Company plc (GEC) – and British Aerospace (BAe) – an aircraft, munitions and naval systems manufacturer.
Relevant evidence: No