E-mail Confidentiality Clause Which Of The Ff. Is The Most Correct Statement About E-mail Confidentiality? A. Once An E-mail Is Deleted, It?

Which of the ff. is the most correct statement about e-mail confidentiality? A. Once an e-mail is deleted, it? - e-mail confidentiality clause

can not be produced and used in a dispute with the client.
b. If an e-mail communications between lawyer and client is not required to be produced during the dispute.
c. If an e-mail is encrypted, can be requested during discovery in litigation
d. If an e-mail is unencrypted, is not considered confidential attorney-client communications.