Answer:
Plant: cells :: language: dialects
Explanation:
The dialect is the composition of a language proper to a region or territory and is related to the linguistic variations found in the speech of certain social groups. In this case, the word "dialect" is the most appropriate to fill in the blank in the questionnaire. This is because "Plants: cells" means that plants are composed of cells, so "language: dialects" means that language is composed of dialects.