Final answer:
The least historical sales data-dependent forecasting method is a market test, which measures real-time performance of a product or service in the market.
Step-by-step explanation:
The forecasting method that is least dependent on historical sales data is e) A market test. Unlike the other methods listed, a market test is designed to collect data on the response of the actual market to a new product or service rather than analyzing trends or cycles from past data. Regression analysis, trend analysis, time series analysis, and cycle analysis are all reliant on historical data to make predictions. In contrast, a market test involves introducing a product or service to a limited audience and measuring its performance in real-time, thus providing predictive information without historical sales data dependence.