What is the basic difference in approach between the Mendeleev's Periodic Law and the Modern Periodic Law?

On the basis of which property did Mendeleev arrange the elements?

What is the importance of the Periodic Table?

Describe Mendeleev's periodic table.

Given below are two statements :
Statement $(I):$ According to the Law of Octaves,the elements were arranged in the increasing order of their atomic number.
Statement $(II) :$ Meyer observed a periodically repeated pattern upon plotting physical properties of certain elements against their respective atomic numbers.
In the light of the above statements,choose the correct answer from the options given below :

"The properties of the elements are periodic function of their atomic numbers." This statement was given by: