Answer:
Why it's not A: We are using generalization of ICBMs. Granted, some may have equal or greater kiloton yield, but generally ICBMs can be traditional missiles, and are not nuclear.
Why it's not B: Not all ICBMs are nuclear, as stated above. The Warheads are usually nuclear or thermal, but it is not always a nuclear weapon.
C. ICBMs can be launched more than a thousand miles away from their target.
ICBMs names imply what they do. They travel "intercontinental", and missiles in today's world suggest using a computer to re-target when needed.
D. Unlike the bombs used during World War II, only a limited number of ICBMs were constructed.
This is only half true. We know that any country can create more ICBMs given time, resources, manpower, and the will to do so. However, Global community keeps each country in regulatory check, to ensure that there are no rogue state being trigger happy to destroy the world.
E. ICBMs are missiles, and the first atomic weapons were conventional bombs.
It's in the name, & it's the game it plays (quite literally). Intercontinental ballistic Missiles can go from one side of the world to another, while the first atomic bombs had to be first dropped by a test tower, and then the next two were dropped from bombers. Nuclear warheads are different from Nuclear bombs.
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