Consider these sentences: Our parents pay for our cell phones.

They like to be in constant contact with us.

Which sentence uses parenthetical elements most effectively to combine the information in the sentences?

Parents (who pay for our cell phones) like to be in constant contact with us.
Parents who pay for our phones (like to be) in constant contact (with us).
Our parents like to be in constant contact with us (even though) they pay—for our cell phones.
Liking to be in constant contact with us, our parents—pay—for our cell phones.