Information:  - New South Wales (abbreviated as NSW) is a state on the east coast of :Australia. It borders Queensland to the north, Victoria to the south, and South Australia to the west. It has a coast line with the Tasman Sea on its east side. The Australian Capital Territory is an enclave within the state. New South Wales' state capital is Sydney, which is also Australia's most populous city. , the estimated population of New South Wales was 7.5 million, making it Australia's most populous state. Just under two-thirds of the state's population, 4.67 million, live in the Greater Sydney area. Inhabitants of New South Wales are referred to as "New South Welshmen".  - The Sydney Tramway Museum is Australia 's oldest tramway museum and the largest in the southern hemisphere , located in Loftus in the southern suburbs of Sydney .  - A tram (also known as tramcar; and in North America known as streetcar, trolley or trolley car) is a rail vehicle which runs on tracks along public urban streets, and also sometimes on a segregated right of way. The lines or networks operated by tramcars are called tramways. Tramways powered by electricity, the most common type historically, were once called electric street railways (mainly in the USA). However, trams were widely used in urban areas before the universal adoption of electrification; other methods of powering trams are listed below under "History".  - Sydney is the state capital of New South Wales and the most populous city in Australia and Oceania. Located on Australia's east coast, the metropolis surrounds the world's largest natural harbour, and sprawls towards the Blue Mountains to the west. Residents of Sydney are known as "Sydneysiders". Sydney is the second official seat and second official residence of the Governor-General of Australia and the Prime Minister of Australia and many federal ministries maintain substantial presences in Sydney.  - Electrification is the process of powering by electricity and is usually associated with changing over from another power source. The broad meaning of the term, such as in the history of technology and economic history, usually applies to a region or national economy. Broadly speaking, electrification was the build out of the electrical generating and distribution systems which occurred in Britain, the United States, and other countries from the mid-1880s until around 1950 and is in progress in rural areas in some developing countries. This included the change over from line shaft and belt drive using steam engines and water power to electric motors.    What object entity has the relation of 'inception' with the subject 'sydney tramway museum'?   Choices: - 1950  - 5  - 7
The answer to this question is:
1950