Question

We will celebrate both __________ birthdays with a single big party.



A.
sister's


B.
sisters'


C.
sisters

Answer 1

this is the same as the last one.

Answer 2

The desert was a sea of color from the __________ blooming flowers.



A.


cacti's


B.


cactis'


C.


cactis



B?

Answer 3

this one would actually be A since the plural of cactus is cacti.