When all the portions of an artwork are combined and seem to function collaboratively, the composition is said to have?

What are your choices?

unity

I agree.

http://arthistory.about.com/cs/glossaries/g/u_unity.htm

When all the portions of an artwork are combined and seem to function collaboratively, the composition is said to have unity. Unity refers to the feeling of harmony and coherence in an artwork, where all elements work together to create a sense of completeness and wholeness. To achieve unity in a composition, artists utilize various visual elements, such as balance, repetition, rhythm, and color harmony. By carefully arranging these elements, artists can create a composition where all the parts work together to convey a unified message or aesthetic.