Final answer:
The underlined word 'creer' means 'to believe' in Spanish.
Step-by-step explanation:
The underlined word in the sentence No puedo creer eso. means to believe. In Spanish, the verb 'creer' means 'to believe' or 'to think'. So, the sentence translates to 'I can't believe that'.
Learn more about Meaning of the word 'creer' in Spanish