Calling H-bombs "fusion" bombs is perhaps a bit of a misnomer in that while fusion is they key component of H-bomb designs most of the energy of these weapons actually comes from fission - the fusion in the secondary produces a large amount of neutrons and these then cause the fission of a uranium tamper around the secondary which is the main energy source.

"fusion" bombs require a fission trigger.

Strontium-90 is, but carbon-14 is formed when nitrogen in the air absorbs a neutron, which could be from either fission or fusion.