Answer:
a) Protons and neutrons are held together inside the nucleus
Step-by-step explanation:
There are four forces which are responsible for all the observations in the nature. These forces are called fundamental forces of nature and listed below:
i) Gravity
ii) Electromagnetism
iii) Weak nuclear force
iv) Strong nuclear force
Among these four, strong nuclear force is strongest one. It has also been observed that when we split nucleus, heat and energy released are larger than any other force. Hence, option (a) will be correct.