Under compatibility rules, transport is forbidden because of excessive sensitivity unless specially authorized. Which option best describes this rule?

• A. The substance has moderate sensitivity
• B. The substance has no explosive properties
• C. The substance is extremely sensitive but can be transported with restrictions
• D. Transport is forbidden because of excessive sensitivity unless specially authorized

Answer: (D)

Excessive sensitivity triggers a blanket prohibition on transport under compatibility rules; movement is only allowed if a special authorization is granted. The statement that transport is forbidden because of excessive sensitivity unless specially authorized matches this exact requirement, making it the best description. The other statements describe different scenarios—moderate sensitivity would not justify a total ban, lack of explosive properties is not the trigger for a transportation restriction, and saying something is extremely sensitive but still transportable with restrictions contradicts the notion of a ban without authorization.