Final answer:
Auscultation and pH testing are the two best ways to test for correct placement of the gavage tube in an infant's stomach.
Step-by-step explanation:
The two best ways to test for correct placement of the gavage tube in an infant's stomach are Auscultation and pH testing.
Auscultation involves listening to the sounds in the stomach using a stethoscope to ensure that the tube is in the correct position.
pH testing involves testing the acidity of the gastric fluid through a gastric aspirate to confirm that the tube is correctly placed in the stomach.