Question

13) The most important active step in the development
of periodic table was taken by :
A) Mendeleev
B) Dalton
C) Avogadro
D) Cavendish.​

Answer 1

Answer:

option no. A is the correct answer mate

Answer 2

Answer:

MENDELEEV.

The most important active step in the development of periodic table was taken by Mendeleev since through others have also made significant contributions towards classification of elements, he elevated the progress made in that direction much more than anyone else.

Thanks...