Identify the word that cannot be formed using the letters of the word 'ENCOURAGEMENT' without repeating any letter more times than it appears in the original word.

Let's count the frequency of letters available in the word $\text{’ENCOURAGEMENT’}$:
$\text{E}\to 3$, $\text{N}\to 2$, $\text{C}\to 1$, $\text{O}\to 1$, $\text{U}\to 1$, $\text{R}\to 1$, $\text{A}\to 1$, $\text{G}\to 1$, $\text{M}\to 1$, $\text{T}\to 1$.

Now, let's check Option D ($\text{COURAGEOUS}$):
It requires two $\text{’O’}$ s and two $\text{’U’}$ s ($\text{C-O-U-R-A-G-E-O-U-S}$). Since the word $\text{’ENCOURAGEMENT’}$ contains only one $\text{’O’}$ and one $\text{’U’}$, and no $\text{’S’}$, $\text{COURAGEOUS}$ cannot be formed.