Last reviewed
Correct answer: C. Sharing anything you want ChatGPT to consider, applied to all your chats
Explanation
The principle — custom instructions are a standing brief, so you stop retyping the same context in every conversation.
Why the key is correct — OpenAI describes custom instructions as allowing you to share anything you would like ChatGPT to consider in its response, and states they are applied immediately to all chats.
Why the others are wrong — nothing here retrains the model, since your guidance travels with your requests and stops mattering the moment you remove it. Capacity and speed come from your plan rather than a text field. And they shape how you are answered rather than acting as a topic filter.
Remember this — anything you find yourself typing at the start of every chat belongs in custom instructions instead.
Sources — OpenAI's ChatGPT Custom Instructions article.
Sources
“Custom instructions allow you to share anything you'd like ChatGPT to consider in its response. Your custom instructions are applied immediately to all chats.”
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