A. 0.5
B. 0.8
C. 1.2
D. 1.5

Correct Answer: Option C

C. 1.2

Explanation

The element B has a mass number of 70 with atomic number 32. Hence, B has 32 protons and (70-32) = 38 neutrons.

The neutron- proton ratio is 38:32 = 38/32 =1.1875
≊1.2

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