Which of the following transitions indicates contrast?

The option that indicates contrast is indeed the one that serves to show a difference or an opposing idea in a discussion. "However" functions as a transitional word that effectively presents a counterpoint to the previous statement. When it is used in a sentence, it signals to the reader that the following information will provide a differing perspective or introduce an exception to what has just been stated. This is essential in writing as it allows for the balance of ideas and helps readers comprehend the nuances of an argument or narrative effectively.

In contrast, transitions like "furthermore," "moreover," and "additionally" serve to build upon or add similar ideas rather than introduce opposing or contrasting thoughts. These words are appropriate for elaborating on points rather than creating a shift in perspective, which reinforces why "however" is the clear choice for indicating contrast between ideas.