This company was the first portable radios as well as cassette tape recorders in the worl

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A. producing
(答案→)B. to produce
C. having produced
D. produced
解析：考查不定式用法。本题考查的是不定式做定语，当名词是序数词或者由序数词修饰的时候，使用不定式做定语修饰该名词。本题前面的名词是序数词the first,故使用不定式修饰。句意：这个公司是世界上第一个生产便携式录音机和盒式录音机的公司。故B正确。