The first thing we are going to do is translate the sentence into English:
My sister _______ in Santa Claus until she was 13 years old.
We now translate the options given in English:
a. heard
c. destroyed
b. believed
d. read
We note that the correct option is option B.
My sister believed in Santa Claus until she was 13 years old.
Therefore, the correct sentence in Spanish is:
Mi hermana creyó en Santa Claus hasta tenía 13 años.
Answer:
Mi hermana creyó en Santa Claus hasta tenía 13 años.
option B