Nosostros (blank) a clase de español todos los días. a) vamos b) ibamos c) fuimos d) iban?

Both "vamos" and "ibamos" could work depending on whether you want the sentence to say "We go to Spanish class every day" or the sentence "We used to go Spanish class every day" respectively. Fuimos cannot work since "todos los dias" requires the imperfect in the past (repetitive activity) and iban cannot work since it is improperly conjugated for nosotros.