-- Hello. Who’s that？ .A. I’m JackB. My name is JackC. Jack speakingD. Rick speaks

问题补充：

-- Hello. Who’s that？ -- .

A. I’m Jack

B. My name is Jack

C. Jack speaking

D. Rick speaks

答案：

A. I’m Jack

B. My name is Jack

(答案→)C. Jack speaking

D. Rick speaks

解析：I’m Jack 我是杰克；My name is Jack 我叫杰克；Jack speaking这是杰克在说话； Rick speaks瑞克说。根据上文，你好，那是谁？英语打电话是常用指示代词this that来指示说话的双方。选项c是This is Jack speaking，的省略形式，故选C。