Which of the following is considered a cult producer in Napa?

Harlan Estate is renowned as a cult producer in Napa Valley, primarily due to its limited production of high-quality wines, a strong following among collectors, and its scarcity on the market. Cult producers typically create small quantities of wine, focusing on exceptional quality and often commanding high prices. Harlan Estate's wines are highly sought after, with vintages often selling out quickly and being hard to find, which adds to their allure and reputation as a cult wine.

In contrast, while some of the other producers mentioned also create respected wines, they do not have the same level of exclusivity or cult status associated with their brands. Hugh Hamilton is known more for its unique varietals in Australia than for a cult status in Napa. Chateau Ste. Michelle is a prominent producer in Washington State, known for its accessibility and larger production volumes. Ridge Vineyards, while respected and well-regarded, particularly for its Zinfandels and Monte Bello Cabernet, does not fit the narrow criteria of a cult winery in Napa, which emphasizes rarity and a high demand among collectors.