Answer:
It can lead to harassment and bullying.
Step-by-step explanation:
Through the internet people can establish conversations with other people they don't know and this situation can lead to harassment and bullying as there is some people that use the anonimity the internet offers to do bad things. Because of that, the answer is that the negative consequence of anonymous communication over the Internet is that it can lead to harassment and bullying.
The other options are not right because the consequences that say that it can lead to regulatory restrictions, to use only the first search results and to cite information without giving proper credit are not related to the anonymous communication over the internet.