Question

which of the following is a major obstacle for law enforcement in investigating internet exploitation?
the offenders rarely repeat their crimes
it is tough to find child pornography on the internet
the internet offers relative anonymity
there is little evidence once the person is identified

Explanation:

The Internet's relative anonymity allows offenders to hide their identities, making it difficult for law enforcement to track them. Offenders often repeat crimes (so the first option is wrong). Child pornography can be found (so the second option is wrong). Once identified, evidence can be gathered (so the fourth option is wrong).

Answer:

The Internet offers relative anonymity.