Answer:

The correct option for specifying an email to be sent is mailto:. The "mailto:" is a URI scheme that allows users to send emails by clicking on a link. It is a simple and convenient way to trigger the default email client on a user's device and populate the fields such as the recipient's email address, subject, and body.

How to use "mailto:" in HTML:
To use the "mailto:" URI scheme in HTML, you can create a link element with the "href" attribute set to "mailto:" followed by the email address. Here's an example:

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When a user clicks on this link, it will open the default email client on their device (such as Outlook, Gmail, or Mail) with the recipient field pre-filled with the email address "example@example.com".

Additional options:
Along with the email address, you can also include additional parameters in the "mailto:" link to pre-fill the subject, body, and other fields. Here are some examples:

1. Specify the subject:
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This will open the email client with the subject field pre-filled with "Hello".

2. Specify multiple recipients:
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This will open the email client with both "example1@example.com" and "example2@example.com" as recipients.

3. Specify the body:
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This will open the email client with the body field pre-filled with "Dear recipient,".

Conclusion:
The "mailto:" URI scheme is used to specify an email to be sent. It allows users to click on a link and open the default email client with pre-filled fields. By using additional parameters, you can customize the recipient, subject, body, and other aspects of the email.