Answer: Correct option is C)
Step-by-step explanation:
Option C is the correct answer because "are" is the second person singular present and first, second, third person plural present of "be", hence for heroes as the plural, it is correct.
Option B is incorrect because "was" is used for singular form only, while heroes is plural.
Option A is incorrect because "is" is used in singular forms.
Option D is incorrect because "had been" means that they had been remembered in the past, and are not remembered anymore, as had been is used for actions that began in the past an d ended in the past
Option E is incorrect because "would be" is for the future, while the heroes are remembered even in the present.
Hope this helped :)