Final answer:
The correct answer is option c. In the provided sentence, 'valediction' means a formal farewell speech or expression, traditionally delivered by the valedictorian during graduation ceremonies.
Step-by-step explanation:
The word “valediction” in the given sentence refers to a “formal farewell speech or expression”. Therefore, the correct answer is (c) A formal farewell speech or expression. A valediction is often associated with graduation ceremonies where the valedictorian, the student with the highest academic achievements, delivers a farewell speech to their classmates, marking the end of an academic period and the beginning of a new chapter in life.
Sam's touching valediction would typically include reflections on past experiences, acknowledgments of accomplishments, and well-wishes for the future to their peers and teachers.