chemical properties

B is correct.

You can think about a periodic table.
Elements are divided into different groups by their number of outermost shell electrons.
eg. The no. outermost shell electrons of sodium is 1, so it is a group I element

Also, elements are divided into different periods by their no. of electron shell occupied.
eg.The no. of electron shells occupied in potassium is 4 (2,8,8,1), thus it is a period 4 element

Now, let's think further about it.
Take group I elements as examples.
In group I, the chemical properties of the elements are similar or even the same.
This explains chemical properties are not related to the no. of electron shells occupied.(i.e period)

In period 3, the chemical properties of sodium(2,8,1) is different from that of chlorine(2,8,7). This explains that elements in the same period have different chemical properties.

So, B is the correct ans

it is depends on the no. of electrons in the outer shell, so is B

Ans:B

electronic arrangement,it means the outermost shell electrons in its atoms.the outermost shell electrons in its atoms=group number