Complete with that followed by the plural simple-past be-passive of damage. Inspectors replaced the windows ___ during the storm. Damage affected several windows.
Ճիշտ պատասխան
that were damaged
Բացատրություն
That refers to the plural windows, so the passive auxiliary were agrees with more than one damaged item. Was would be singular and would clash with both the plural antecedent and the premise about several windows.