I had to put the answer in the image sorry
Answer:
The pitch of a sound is how high or low a sound is when we hear it, whereas the intensity of a sound is the energy/vibrancy of the sound over an area and depends on the frequency of the sound as well.
The answer is; medulla oblongata and pons.
In this region of the brain, there are chemoreceptors that can detect changes in the pH of the blood. These are called central chemoreceptor. There are also chemoreceptors in the arteries called peripheral chemoreceptors. When these chemoreceptors detect a drop in the blood PH (due to increased dissolved carbon dioxide in the blood), the depth and rate of breathing is increased in the lungs.