The elements on the right side of the periodic table are

The long form of the periodic table is based on:

The atomic number of the element unnilennium is

Which among the following electronic configurations belong to main group elements?
$A. [Ne] 3s^1$
$B. [Ar] 3d^3 4s^2$
$C. [Kr] 4d^{10} 5s^2 5p^5$
$D. [Ar] 3d^{10} 4s^1$
$E. [Rn] 5f^0 6d^2 7s^2$
Choose the correct answer from the options given below:

In which group of the periodic table will the element with $Z=120$ be placed?

What is the maximum number of elements possible in a period? Where are they located?