$E_{Ge}, E_{Si}$ and $E_C$, denote the ionization energy values for Ge, Si and C, respectively. The values correctly arranged in increasing order are as in option.

$E_{Ge}, E_{Si}, E_C$

The correct answer is Option (4) → $E_{Ge}, E_{Si}, E_C$

Ionization energy decreases down the group in the periodic table because the atomic size increases and the attraction between the nucleus and the outermost electron decreases.

Since C, Si, and Ge belong to Group 14 (carbon family):

$E_{Ge} < E_{Si} < E_{C}$

Answer: $E_{Ge}, E_{Si}, E_{C}$