Which of the following is an advantage of implementing Google Tag Manager?
You can add Google Analytics tags to your site without editing site code.
You can add AdWords tags to your site without editing site code.
You can add non-Google tags to your site without editing site code.
You can change configuration values in your mobile app without rebuilding a new binary.
All of these answers are correct.
Which of the following is an advantage of implementing Google Tag Manager
Explanations:
You should always start with a measurement plan that details the data you want to collect. This will help you report the performance of your business objectives and key performance indicators (KPIs) to your stakeholders. If you’re new to measurement planning, check out Analytics Academy for tips on how to create a solid measurement plan.
Once you’ve defined a measurement plan, you’ll need to create a container and place the GTM container code on your website
Source
You can read more here: https://support.google.com/analytics/topic/6163649?hl=en