Detailed Instructions: In this task you will be given an answer to a question. You need to generate a question. The answer given should be a correct answer for the generated question.
Q: Inhalation or inspiration, begins when cells of the solitary tract nucleus (along with cells of the ventral respiratory group) begin a steady increase in firing, leading to contraction of the respiratory muscles. When neurons in the DRG are activated they send impulses down the phrenic and intercostal nerves to stimulate the diaphragm and external intercostal muscles. The thoracic cavity expands and air rushes into the lungs due to the negative pressure, producing inspiration. When the cells stop firing, the respiratory muscles relax, inhalation ceases, and exhalation begins.
A:
which center stimulates inspiration by increasing the activity of the dorsal respiratory group (drg)