Final answer:
Gamma rays have the highest frequency among the given options.
Step-by-step explanation:
The waves with the highest frequency among the given options are gamma rays (option d).
Electromagnetic waves are classified based on their frequency, with gamma rays having the highest frequency. Gamma rays have frequencies in the range of about 10^19 Hz or higher.
In contrast, radio waves have the lowest frequency among the options, and microwaves and infrared waves have higher frequencies compared to radio waves but lower frequencies compared to gamma rays.