The Y stem-changing verbs in Spanish are those that undergo a change in the present tense when they are conjugated. The stem-changing verbs get their name because the stem vowel changes to "ie" or "i" when conjugated, except in the nosotros and vosotros forms. Out of the options given, the Y stem-changing verb is "Perder." Let's take a look at how it changes in the present tense: - Yo pierdo (I lose) - Tú pierdes (You lose) - Él/Ella/Usted pierde (He/She/You formal lose) - Nosotros/Nosotras perdemos (We lose) - Vosotros/Vosotras perdéis (You all lose) - Ellos/Ellas/Ustedes pierden (They/You all lose) As you can see, the stem vowel "e" in "Perder" changes to "ie" in the conjugations except for the nosotros and vosotros forms.