lib/mail/Mail.php
public function addCcs(
        $ccEmails,
        $personalizationIndex = null,
        $personalization = null
    ) {
        $this->addRecipientEmails(
            "Cc",
            $ccEmails,
            $personalizationIndex,
            $personalization
        );
    }
public function addCcs(
        $ccEmails,
        $personalizationIndex = null,
        $personalization = null
    ) {
        $this->addRecipientEmails(
            "Cc",
            $ccEmails,
            $personalizationIndex,
            $personalization
        );
    }
public function addCcs ( $ ccEmails , $ personalizationIndex = null , $ personalization = null ) { $ this -> addRecipientEmails ( "Cc" , $ ccEmails , $ personalizationIndex , $ personalization ) ; }
Adds multiple email cc recipients to a Personalization object

@param Cc[]|array $ccEmails Array of Cc objects or
key/value pairs of email
address/recipient names
@param int|null $personalizationIndex Index into an array of
existing Personalization
objects
@param Personalization|null $personalization A pre-created
Personalization object
Adds multiple email cc recipients to a Personalization object