What is the appropriate action to include all recipients in a response to a copied email?

Using the "Reply All" option is the appropriate action when you want to include all recipients in your response to a copied email. This function allows you to respond not only to the original sender but also to everyone else who received the email. By doing so, you ensure that all parties involved in the conversation remain informed and can continue the dialogue without missing anyone.

This is particularly useful in group discussions or team communications where it’s important for every participant to stay updated on responses and contributions. It facilitates collaboration and avoids confusion about who has received the latest information.