Answer:
B
Explanation:
neutrons + atomic number/proton/electron for a neutral atom = mass number
e.g
mass number of Chlorine 35.5
proton number 17
neutron number will be 35.5-17 = 18.5
Therefore.....
your question deduced says
atomic number is 5
mass number is 11
neutron number is however mass number minus atomic number 11-5 =6
