What are the techniques for anesthetic monitoring in dogs and cats?

The use of anesthetic monitoring equipment is essential to recognize accidents and complications, consider their severity and therapeutic options, and evaluate the response to treatment.
The use of visual techniques, such as observing chest excursions, is the most basic way to detect respiratory movements.
The use of sound devices, such as the esophageal stethoscope and the apnea monitor, allows for the detection of respiratory movements and frequency.
The use of spirometry or ventilometry allows for the continuous and immediate measurement of tidal volume, respiratory rate, and minute volume.
a) Only I and II are correct.
b) Only II and III are correct.
c) Only III and IV are correct.
d) All statements are correct.