undifferentiated marketing. Undifferentiated marketing is a strategy in which market segments differences are ignored and one product or service is offered to the entire market.
The Secretary of State, Secretary of the Treasury, Secretary of Defense, Secretary of Interior, Secretary of Agriculture, Secretary of Commerce, etc. are cabinet level positions in the president's cabinet. There are currently 15.
There is also discussion of the Ambassador to the United Nations and the Director of National Intelligence holding 'Cabinet level rank', so, depending on how one wants to define their participation in the Cabinet, the answer can range from 15 to 23. The next presidential administration may amend this further.