[解析]
(1)推理判断题。根据第一段Obviously television has both advantages and disadvantages.(显然,电视既有优点也有缺点。)可知,文章主要讨论的是电视的优点和缺点,即第一段的主要目的是介绍整篇文章的主题。故选B。
(2)细节理解题。根据第二段In the first place,television is not only a convenient source of entertainment,but also a comparatively cheap one.(首先,电视不仅是一种方便的娱乐来源,而且相对便宜。)可知,作为娱乐的一种来源,电视相对便宜。故选D。
(3)细节理解题。根据第三段Television,it is often said,keeps one informed about current events and the latest developments in science and politics.(人们常说,电视使人们了解科学和政治方面的时事和最新发展。)可知,电视最明显的优势之一是它让我们随时了解情况。故选A。
(4)推理判断题。根据最后一段We must realize that television itself is neither good nor bad.It is the uses that it is put to that determine its value to the society.(我们必须认识到电视本身没有好坏之分。它的用途决定了它对社会的价值。)可知,电视是否好取决于我们如何使用它。即人们对它的态度,故选B。