Final answer:
The widespread belief in Nessie is most likely due to media influence, which amplifies interest and belief through sensational coverage and anecdotes, despite a lack of concrete scientific evidence.
Step-by-step explanation:
The most likely explanation for the widespread belief in Nessie, also known as the Loch Ness Monster, is (c) Media influence. While there may be some cultural folklore and historical records that mention creatures similar to Nessie, the preponderance of evidence suggests that media portrayal has significantly amplified interest and belief in Nessie's existence. Unlike scientific evidence which is based on empirical findings and rigorous testing, the belief in Nessie persists even in the absence of concrete physical evidence. Instead, phenomena of Nessie's type are typically perpetuated by sensational media coverage and anecdotal testimonials rather than validated scientific data, leading to a kind of preferred status in popular culture.