Which fundamental force causes some forms of radioactivity? A. Gravity B. Electromagnetic force C. Strong nuclear force D. Weak nuclear force?

Hello.

The answer is: D. weak nuclear force.

The weak force causes beta decay, a form of radioactivity. It could not be explained by the strong nuclear force, the force that's responsible for holding the atomic nucleus together, because this force doesn't affect electrons.

It couldn't be the electromagnetic force, because this does not affect neutrons, and the force of gravity is far too weak to be responsible.

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