Answer:
a carpenter using saws and cutting tools
Explanation:
In noise cancelling system we know that two sounds are cancelled just by using the concept of destructive interference.
Here when two sounds which are in opposite phase are superimposed with each other then due to this superposition of waves the resultant intensity will be less than the intensity of any individual wave.
This phenomenon is known as destructive interference.
This is used to decrease the level of sound in such a part of work where we have large sound in output so here correct answer will be
a carpenter using saws and cutting tools
This is because it produce large noise while we use this cutting tools