Answer:
Hello, and the answer should be Dynamics and Accelerando. Reason is, Dynamics is is a variation of loudness and quietness. So, that goes perfectly with Crescendo and Decrescendo. With Accelerando that's dealing with the sound also. I hope you have a nice day! Also, if you could mark me as brainliest that'd be great, it's up to you though ! :)
Explanation:
