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Question No. 4
Which of the following forces is responsible for beta-decay?
A. Electromagnetic force
B. Strong nuclear force
C. Weak nuclear force
D. Gravitational force

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The role of the weak?force?in the transmutation of quarks makes it the interaction involved in many?decays?of nuclear particles which require a change of a quark from one flavor to another. It was in radioactive?decay?such as?beta decay?that the existence of the weak interaction was first revealed.