<p>I found the question/answer. Notice the part about (B), though I do see where you were coming from.</p>
<p>Explanation</p>
<p>Be alerted by the semicolon separating the two clauses in this sentence. Remember, a semicolon can only be used if the two halves of a sentence are independent and able to stand on their own. The first half of the sentence is the left-handed can opener was a brilliant invention; this is a complete sentence. The second half reads the popularization of electric can openers made it obsolete, however. This is also an independent clause. The word however does dangle on the end, but it does not violate any major rule of correct English usage. There is no error in this sentence, and choice A is the correct answer. Choice B is wrong because it includes the word but, which makes the second sentence a dependent clause. Recall that in order to use a semicolon, the two halves of a sentence must be independent of each other. Choice C introduces the word and. However, the two halves of the sentence are intended to show some contrast; while the left-handed can opener was a brilliant invention, electric can openers rendered that great invention obsolete. The word and does not adequately demonstrate this contrast. Choice D is problematic because it is not clear what the pronoun it refers to; a pronoun must have one clear antecedent. Choice E includes the wordy and awkward phrase however obsolete it was.</p>
<p>Edit- It came from <a href=“http://testprep.sparknotes.com/powertactics/writingmc/chapter11.epl[/url]”>http://testprep.sparknotes.com/powertactics/writingmc/chapter11.epl</a> by the way</p>