I can try.
Whats the question
Mass number = number of protons + number of neutrons
mass number= 8 + 7= 15 ---> the answer is B.
The name of that product is 1-nonene.
The sufix ene is because it is an alkene, which comes from the fact that it has a double bond.
The prefix none is because it has 9 carbon.
And the use of number 1 is because the double bond is in the carbon number 1.