Answer:
D) aggregating.
Step-by-step explanation:
Market aggregation is basically reverse market segmentation. One of the possible errors that companies can make when segmenting a market, is that they keep segmenting similar segments into smaller groups. Once they realize that they segmented their markets too much, they go back and aggregate small market segments into larger ones.
In this case, Toyota segmented their young customers into 4 separate segments and after they realized that it didn't make sense since the 4 groups were basically identical, they reversed their decision and formed one single larger segment.