This question asks you to pick the answer choice which does NOT support the claim in question. That claim is: Criminals who commit crimes via computer are unlikely to be both arrested and convicted even if they are discovered and reported.
Answer (A) supports this claim tangentially. It tells us that prosecutors are evaluated by the number of cases they do. If the goal is more cases, you want lots of cases that don't take very long, not a few cases that take a long time. Computer fraud cases take a long time, so the prosecutors aren't incentivized to take them.
Answer (D) does not support the claim at all. The claim is about the likelihood that computer criminals are arrested and convicted. This answer is about the likelihood that computer criminals are sentenced to serve time in prison. Sentencing is not the same as arrests or convictions, so it doesn't support the claim.