Answer:
I think the right answer was "because they have already formed bonds to become more stable"
Step-by-step explanation:
the reason you got the question wrong was because not all unstable elements have to be bonded with a gas molecule. It could be a metal for example.
it's hard to find these unstable elements in natural nature because since they are so unstable, they can't "wait" so they form bonds as soon as they can when they get the chance.
nature isn't controlled by scientists too, so these unstable elements form bonds with almost anything possible when they have the chance to become more stable