Final answer:
The option not indicating a potentially negative impact of tourism is 'Keeping local culture and traditions alive,' which is generally viewed as positive, in contrast to the loss of cultural authenticity, urbanization, and emigration encouragement, health risk increases, and commercialization of hospitality customs.
Step-by-step explanation:
The potentially negative social and cultural impact of tourism that is not listed is 'Keeping local culture and traditions alive.' This is generally seen as a positive outcome of tourism. Negative impacts can include the loss of cultural authenticity because local cultures may become commercialized as they cater to tourist expectations, which often leads to a standardized or inauthentic cultural experience. Another negative impact is the encouragement of urbanization and emigration, often leading to over-development and the depletion of local resources. An increase in health risks is also a concern as large influxes of tourists can lead to greater pollution and strain on local health care services. Finally, the commercialization of traditional welcome and hospitality customs can occur, whereby local traditions are commodified and presented in a manner that may dilute their original significance and value.