Which would make the most appropriate transition word or phrase to place in front of the second sentence in selection one

As you've not provided a specific text or context, I cannot provide a specific transition word or phrase. However, common transition words or phrases include "However," "Moreover," "In addition," "On the other hand," "For example," "Then," "Next," "Thus," "Therefore," "Furthermore," "In other words," etc. Choose the one that accurately reflects the relationship between the two sentences. There is a variety depending on whether you are adding to an idea, giving examples, contrasting, or concluding a thought.

To determine the most appropriate transition word or phrase to place in front of the second sentence in selection one, we would need the specific sentences of selection one. Kindly provide the sentences, and I'll be happy to assist you further.