Which of the following statements is false?
a. the dictionary definition of a word is its denotation.
b. the cultural or contextual meaning of a word is its connotation.
c. every word has a positive or negative connotation.
d. word connotations can be positive or negative.

I would say C. The connotation of the word, or the feelings implied when you hear it can be neutral. For example, if you read the word bread, would you feel happy or sad? Well, not really you would feel neutral about it. 
A is true denotation is the definition B is true of connotation aforementioned D Word connotations can be positive and negative, but can also be neutral so that is true