re instant is the response to how it works. For example, door invites knob, lamp invites shade, plant invites water. Furthermore, if the person gives an opinionated answer like fun or gross, the answer is also contiguous. So it seems to me the odds are in favor of contiguous answers.
You may be tempted to assign procedural, inside the box vs. non-procedural outside the box thinking to the two types of word choices. There are too many variables to form that conclusion. For instance, someone who is really good at something–playing the piano, for example–is likely to compliment the word piano with one of its prominent features. That would be a contiguous answer. Overall, in terms of general language usage, Jakobson says, “In manipulating the two kinds of connection (similarity and contiguity). . .an individual exhibits his personal style, his verbal predilections and preferences.” 1
The important thing is just to have fun with this activity. Kids are generally tickled by the idea. It gives them an opportunity to play with words, so to speak. Furthermore, using the answers to play rhyming games is a wonderful way to increase familiarity with words and the sounds they make. If you keep score, the activity also provides exposure to simple addition, as well as exposure to the concept of less than, greater than (when comparing totals).
Best of Luck – have fun!
1. Jakobson, Roman. “Two Aspects of Language: Metaphor and Metonymy.” European Literary Theory and Practice- From Existential Phenomenology to Structuralism. 1st ed. New York, New York: Dell Publishing Co., Inc., 1973. Print.