Frecuentemente al cine. (ir)(in a past tense)

The correct answer is:  " íbamos " .

       " Nosotros  íbamos  frecuentemente al cine. "

Note the Spanish word:  "frecuentemente" .

  In the past tense, this translates to:  

"We frequently went to the movies [movie threatre]" .

However, note that this type of past tense translates as:

"We frequently would  go to the movies". 

This is how to translate the past tense when the word "frequently" {"frecuentemente" — in Spanish } — is used.

So, we use the "present imperfect past tense" conjugated form of the Spanish verb, "ir" (to go); that corresponds with the "first person, plural" subject pronoun";  which is:  "we" — {in English} ; or, "nosotros" (as directly given) or "nosotras" (in some cases) — {in Spanish} .

→  The correct conjugation is:  " íbamos " ;  and:


→  The correct answer is:  " íbamos " . 

Hope this answer — and explanation — is of help to you.
   Best wishes in your academic pursuits and in the community!