It was not until 1938 the first colour TV programme was broadcast.A. whichB. thatC. when

问题补充：

It was not until 1938 the first colour TV programme was broadcast.

A. which

B. that

C. when

D. on which

答案：

A. which

(答案→)B. that

C. when

D. on which

解析：

试题分析:考查强调句型。从句意可知即使不填选项，句子意思仍然完整，所以判断为强调句型。强调句型的特点是去掉it is ….that 部分，句意完整通顺，所以答案为B。句意：直到1938年第一个彩色电视节目才被播出。