Final answer:
The sales forecast should be primarily based on statistical analysis. Input from sales managers and representatives can supplement the forecast, but it is not the main method used. Production capacity and input from the board of directors are not directly related to sales forecasting.
Step-by-step explanation:
The sales forecast should be primarily based on statistical analysis. By analyzing historical sales data and market trends, businesses can make informed predictions about future sales. This method uses mathematical models and statistical techniques to identify patterns and forecast future sales figures.
While input from sales managers and representatives (option B) is valuable, it should be used as a supplementary source of information to validate and refine the forecast. Production capacity (option C) is more relevant for planning operational activities and ensuring the ability to meet customer demand, but it is not directly related to forecasting sales.
Input from the board of directors (option D) may be considered in strategic decision-making, but it is not the primary source for sales forecasting.