The error in the possessive construction is that, instead of passenger's, it should be "passengers'". The apostrophe should be after the letter "s" because the noun is in the plural form. The correct sentence would be "Passengers' concerns about cell phone use on planes are justified."
Answer:
The cat's tail.
Explanation:
Possessive form usually means you add 's to the end of the noun that owns the object. You always put the noun directly in front of the thing that it owns in possessive form.