"WiMAX" is the correct answer for the above question.
Explanation:
WiMAX is a broadband wireless technology that follows the IEEE standard. This full form of this technology is "Worldwide Interoperability for Microwave Access".
This technology is used to control the media and provide the physical layer.
The above question asked about the term which follows the IEEE standard. So the term is "Wimax"
The answer is 2-to-the-power-of-n, since for every input, the number of different combinations doubles. From your list I think answer A is meant to indicate 2ⁿ.
