A suburb is a residential district located on the outskirts of a city. If you live in the suburbs, you probably travel to the city for work. Suburb comes from Latin: sub means "below or near" and urbis means "city." You also will recognize this root in urban.
suburb or suburban area is a mixed-use or residential area, existing either as part of a city or urban area or as a separate residential community within commuting distance of a city. ... Suburbs tend to proliferate around cities that have an abundance of adjacent flat land
The answer is A. When it comes to importing agricultural goods I think u would need advanced heavy automobiles to move the goods into the country so I don't think B C or D are correct.