Final answer:
The verb perder undergoes the e-ie stem change in the present tense conjugation.
Step-by-step explanation:
The stem change that applies to the verb perder is e-ie. Stem changes occur in certain Spanish verbs when conjugating them in the present tense. In the case of perder, the stem e changes to ie in all forms except the nosotros and vosotros forms.
Learn more about Spanish verb conjugation