Which of the following figures represents Mendeléev's Periodic Table that was published in a German journal in 1872?

The correct option is c.

Explanation:
In 1872, Dmitri Mendeléev published a revised and comprehensive version of his Periodic Table in a German chemical journal (Annalen der Chemie und Pharmacie).

The main structural characteristics of Mendeléev's 1872 Periodic Table were:
1. Groups: The vertical columns were divided into 8 groups labeled with Roman numerals from I to VIII. Group VIII specifically housed triads of transition elements (such as Fe, Co, Ni in period 4; Ru, Rh, Pd in period 5; and Os, Ir, Pt in period 6).
2. Periods: The horizontal rows were divided into 6 periods (numbered 1 to 6).

By inspecting the provided figure:

• Figure (a) displays only Groups I to VII.
• Figure (b) displays only Groups I to VI.
• Figure (c) displays Groups I to VIII across Periods 1 to 6, with Group VIII blocks present in periods 4, 5, and 6. This perfectly matches the structure of Mendeléev's 1872 table.
• Figure (d) displays Groups I to IX, which includes an extra non-existent group.

Hence, Figure (c) is the correct representation.