Question

Which of the words has the most negative connotation

Answer 1

Oops! You left out the words! However, I can still help :) 
First, you have to know the definition of connotation. You might be more familiar with Denotation which is the dictionary definition of a word. 
Connotation however, is the way a word makes you feel. 

For example, talkative and conversational pretty much mean the same thing. More than likely though, you see talkative as a bad quality and conversational as more of good quality. 
The word with a negative connotation would be talkative. 
The word with a positive connotation would be conversational.