Choose the sentence that is correctly punctuated.
a.
this article argues that there are some interesting similarities between lincoln and kennedy's assassinations.
b.
this article argues that there are some interesting similarities between lincolns and kennedys assassinations.
c.
this article argues that there are some interesting similarities between lincoln's and kennedy's assassinations.
d.
this article argues that there are some interesting similarities between lincolns' and kennedys' assassinations.

C.  This article argues that there are some interesting similarities between Lincoln's and Kennedy's assassinations.

Explanation:

When talking of something in the possessive noun, it is mandatory to indicate the apostrophe s ('s) in the primary noun. So, for the above sentence to be grammatically correct, we will have to add 's to both Lincoln and Kennedy as they comprise of separate persons.

This article argues that there are some interesting similarities between Lincoln's and Kennedy's assassinations.

The addition of the 's in the respective names of the two men indicate their respective assassinations.  

the god   the goddess of salt water, of fresh water   yet more powerful and perfect.

its a hard situation i cant really answer because the essay is for you to write.