In a narcotics conspiracy prosecution against Daly, the prosecutor offers in evidence a tape recording of a telephone call allegedly made by Daly. A lay witness is called to testify that the voice on the recording is Daly's. Her testimony to which of the following would be the LEAST sufficient basis for admitting the recording?
She had heard the same voice on a similar tape recording identified to her by Daly's brother. She had heard Daly speak many times, but never over the telephone.  She had, specifically for the purpose of preparing to testify, talked with Daly over the telephone at a time after the recording was made.  She had been present with Daly when he engaged in the conversation in question but had heard only Daly's side of the conversation