Apple lets you better control Siri’s responses by allowing the assistant to deliver quiet responses. This is useful if you’re in a low-noise environment or sensitive environments where silence is a top priority. If you want Siri to be quieter on your iPhone, this is the perfect guide for you.
iPhone 12: How to Set Siri Voice Responses to Always/When Silent Mode is Off/Only with 'Hey Siri'
You can follow the guide below to make Siri answer your questions with silent answers.
Additionally, we recommend turning on the toggle for Always Show Siri Captions and Always Show Speech to better understand Siri's responses when she responds silently. However, this is completely optional and you can leave these options turned off if you prefer.
And that’s it! Siri now responds silently when you activate a task on your iPhone.