In the process of software production, the sources of demand information are A programmer, B project manager, C designer and D software users.

Select project manager B. In the production process, the user's demand and design scheme have been decided, and they are all in the hands of the project manager. Designers do not need to communicate directly with users to obtain demand information. Only in the early stage of software planning, the project manager or other business personnel will directly communicate with users to obtain demand information.