An app builder wants to add the option to ' Send New Email ' from...

Global actions are designed to be available broadly, not only from one object’s record page. Salesforce Trailhead states that global actions can be placed anywhere actions are supported and can let users send email without leaving the page they are on.

This fits the requirement because users need a Send New Email action available from Leads, Contacts, and Accounts in the Salesforce mobile app.

Why others are incorrect:

A is incorrect because a global action layout does not automatically clone the default page layout.

B is incorrect because the Lightning Component Library is not the reason to use global actions.

C is incorrect because global actions are not record-specific; object-specific actions are record-specific.

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