In the following output from top, which processes contribute to the percentage of time that the CPU spends in the state of wa?

In the following output from top, which processes contribute to the percentage of time that the CPU spends in the state of wa?

Tasks: 193 total, 1 running, 190 sleeping, 2 stopped, 0 zombie

Cpu(s): 0.5%us, 0.3%sy, 0.0%ni, 98.2%id, 1.0%wa, 0.0%hi, 0.0%si, 0.0%st
A . Processes waiting for user interaction.
B . Processes that were already closed and are waiting to be launched again.
C . Processes that have not been scheduled yet because they haven’t been fully loaded into RAM or are in swap.
D . Processes waiting for IO operations to complete.

Answer: D