Which sentence contains an incorrect possessive form?

a.
his solution took everybody's objections into account.

b.
it looks as though that calf has wandered away from its mother.

c.
the credit for the decorations is all hers'.

d.
someone's bike is in the driveway.

me dude.

C.  The credit for the decorations is all hers'.

Explanation:

Hers does not require the apostrophe.   It is a possessive pronoun, and they are used without the apostrophe.    

Answer choices A, B, and C are good.  

explanation: yee yee

"get off of your lazy bum and come running with me or i'm dumping this pitcher of water on u " u say with a smile. she thinks your joking so she ignores you about 10 seconds later shes screaming wile water is dripping everywhere you say "here comes the second one! " then you here her say okay, your such a j e r k ! ill be ready in 5 put the pitcher down " she say in an angry tone. and you smile in victory

good enough?