As for this problem concerning about a transition between sentences and paragraphs, the most probable and most likely to be the answer out of the options presented would be the third one which is a bridge.
A transition serves as a bridge between sentences and paragraphs. Though they create a divide between them, these transitions do not necessarily indicate that the divide is to cause to present that the two aren't connected to each other. A summary and introduction wouldn't do since a transition functions more and effectively between sentences and paragraphs.
Answer:
Like electric charges repel each other. ... Why can't conductors generate static electricity when rubbed together? They will direct excess charge to earth. Suppose you acquire a positive charge from walking across a carpet.
I think c) uses contrasts <span>between darkness and light to highlight his points.</span>
