Final answer:
From the options given, trend extrapolation is the statistical method used for sales forecasting, which analyzes past sales data to estimate future sales.
Step-by-step explanation:
The statistical method used for sales forecasting from the given options is trend extrapolation. This technique involves extending historical data into the future to predict upcoming trends.
It does not include surveys of buyers' intentions, a lost-horse forecast, or a salesforce survey forecast but it's a type of direct forecast. While all of these can be methods for forecasting sales, trend extrapolation specifically uses statistical techniques to analyze past sales data and project this into the future to estimate future sales.