Nuclear and/or radiological weapons are extremely difficult to obtain; these threats are considered to be a low threat relative to other terrorist weapons.

• A. High
• B. Moderate
• C. Low
• D. Unknown

Answer: (C)

The idea being tested is how risk is judged by how likely something is to happen, not just how bad it would be if it did. Nuclear and radiological weapons have the potential for catastrophic damage, but they’re extremely hard to obtain and deploy. The barriers—advanced technology, high costs, strict controls, and the need for specialized expertise—make the probability of a terrorist group actually acquiring and successfully using such weapons very low compared with more accessible threats. In risk assessments, this low likelihood means the overall threat level is considered low, even though the potential impact is enormous. So, despite the high consequence, the correct classification here is low because the chance of occurrence is judged to be small.