Final answer:
The least effective method to enhance children's and adolescent's ability to understand spoken language would be watching movies without subtitles. Subtitles can support language learning, while storytelling, role-playing, and listening to audiobooks involve more interactive and contextual language practice.
Step-by-step explanation:
If one wanted to enhance children's and adolescent's ability to understand what other people say, the least likely method to use among the four options provided would be watching movies without subtitles. While options such as storytelling, role-playing, and listening to audiobooks actively engage children and adolescents in the language acquisition process, watching movies without subtitles might not provide the necessary support for those still learning the language. Subtitles can serve as a learning tool that reinforces understanding through reading along while listening.
Storytelling can be particularly effective as it involves a reciprocal interaction with the listener that can be tailored to the developmental level of the child or adolescent. Role-playing can enhance language skills by putting children and adolescents in situations where they have to use language in context, which is essential for proper language acquisition and socialization. On the other hand, listening to audiobooks can improve listening skills and vocabulary but lacks the interactive and contextual elements provided by the other methods.