The stability of an atom is determined by the: a strength of its gamma rays b ratio of neutrons to protons c number of electrons in the outer shell d attraction between neutrons and electrons

Your correct answer is (B) Ratio of neutrons to protons

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B ratio of neutrons to protons

Explanation:

The stability of an atom is determined by the ratio of neutrons to protons in the nucleus of an atom. The lager the ratio of neutrons to proton the lesser is the stability of the nucleus. The n to p ratio of higher atomic number that exist in a number of isotopic form is higher and their stability is low. The uranium 238 breaks down to lead 206.  

since electrons are negative the answer is neagtaive