A conurbation is a large urban area where several towns or cities have grown and merged together over a significant geographical area. This results in a continuous urban environment that functions as a single economic, social, and administrative unit. It is characterized by not only the physical merging but also the economic and social integration of these urban areas. Importantly, while these towns join together, they often retain their individual identities to some extent, but collectively they function as a larger urban zone.
Hence, the most accurate explanation is that a conurbation is a settlement where a large number of towns join together over a considerable area. This results in significant density and sometimes shared infrastructure and services. It is not merely about the number of people, nor does it focus primarily on an agricultural economy (such as predominantly farmers). Likewise, even though two or more towns combine, the emphasis is on the large-scale joining and integration process across numerous towns, rather than solely retaining distinct identities.