Answer:
Option A. Potassium.
Step-by-step explanation:
The electronic configuration of the element given above is:
1s2 2s2 2p6 3s2 3p6 4s1
To know which element has the above electronic configuration, we simply calculate the atomic number of the element. This can be obtained by adding the electrons in the electronic configuration as follow:
2 + 2 + 6 + 2 + 6 + 1 = 19
The atomic number of the element is 19.
Atomic number is the identity of elements in the periodic table. No two elements have the same atomic number.
Therefore, the element is Potassium because only potassium has atomic number of 19 in the periodic table.