Final answer:
The best transition word to replace 'likewise' is 'therefore' because it clearly shows the consequence of running deceptive content, which is reader distrust. The answer is B. therefore.
Step-by-step explanation:
The sentence is saying that many websites post deceptive ads, and this can cause distrust in readers. The word "therefore" is a conjunctive adverb that means "as a result of this." It is used to connect two ideas that are related cause and effect. In this case, the cause is the deceptive ads, and the effect is distrust in readers.
The other answer choices do not make sense. "No change" means that the sentence is correct as it is. "However" is a conjunctive adverb that means "but" or "on the other hand." It is used to contrast two ideas. "Especially" is an adverb that means "to a great extent." It is used to emphasize something. None of these answer choices are appropriate for the sentence.
Therefore, the correct answer is B. therefore.