Answer:
Hace tres meses que vivimos aquí.
Step-by-step explanation:
The sentence is using Present Perfect Tense, which is use to express unfinished actions. So, the right answer must express that too but in Spanish. The fourth answer is expressing an unfinished actions, the third one doesn't, and other options are grammarly wrong.
Therefore, for the sentence "We have lived here for three months", the best answer is "Hace tres meses que vivimos aquí". However, we could also say "Hemos vivido aquí por tres meses".