Final answer:
A contrasting transitional phrase introduces opposing or contradictory ideas. 'On the contrary' is an example of such a phrase, while 'So' and 'In addition' are additive transitional phrases
Step-by-step explanation:
A contrasting transitional phrase is one that shows a contradiction or opposition between two ideas. In this case, the phrase 'On the contrary' is a contrasting transitional phrase because it introduces an opposing or contradictory idea to the previous statement. For example, 'She said it was going to rain, but on the contrary, it turned out to be a sunny day.' On the other hand, 'So' is an additive transitional phrase that shows a cause and effect relationship, while 'In addition' is an additive transitional phrase that introduces an additional idea.
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