What is the difference between these two buttons?

Select one:

The To field will have the email addresses of one or more reciplents, the email address in the CC field will be hidden from everyone else

The To field will have the email addresses of one or more recipients, the email addresses In the CC field are added for them to get the information in the email

There is no difference

The To field will have the email address of only the first reciplent, the CC field will have the email address of the next recipient