What kind of questions does a call center ask during a phone interview?

It depends upon your domain, most of the times telephonic interviews are for voice assessment and to check voice modulation. In telephonic interview they can ask you to go through your cv or reason for leaving previous job or may be what you expect from us.
I started one thread few days ago, you might like to check it: BPO Interview Questions and Answers

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Aditya Rana
India BPO Forum

its all depends on organization and process for that they are hiring

It is depends on the policy of your organization. Sometimes agents are just following what their supervisors ask them to do.