Final answer:
Option d) 'contain important clues about what will happen in the future' is the statement of opinion, being speculative and not empirically supported, unlike the other fact-based options.
Step-by-step explanation:
Option d) 'contain important clues about what will happen in the future' is the statement of opinion, being speculative and not empirically supported, unlike the other fact-based options.
Regarding the question, Which of these is a statement of opinion? the correct answer is option d) contain important clues about what will happen in the future. This statement is subjective and not objectively verifiable with scientific methodologies. Statements a), b), and c) describe aspects of dreaming that are either observable during sleep (such as REM stage), supported by empirical evidence (people experiencing dreams), or discuss scientific explorations (theories about dreaming). The opinion in option d) is speculative and not grounded in empirical science, making it a departure from the fact-based nature of the other options.