Atty. X fails to serve personally a copy of his motion to Atty. Y because the office and residence of Atty. Y and the latter's client changed and no…

The question

Atty. X fails to serve personally a copy of his motion to Atty. Y because the office and residence of Atty. Y and the latter's client changed and no forwarding addresses were given. Atty. X's remedy is to:

1. A.Serve by registered mail;
2. B.Serve by publication;
3. C.Deliver copy of the motion to the clerk of court with proof of failure to serve;
4. D.Certify in the motion that personal service and through mail was impossible.

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