Which of the following transitional expressions indicates a result or cause? A. Actually B. Therefore C. All in all D. However

The right answer is Therefore. A transitional expression is a word or phrase that relates the meaning of one sentence to the meaning of the following one. Therefore is an example of it and it means as a result, for that reason which clearly indicates a cause of something. For example: we were not able to stop the fire therefore the house got burnt. In this case we make clear that the fire caused the burning of the house.