Which word cannot be formed from DEMOCRACY?

The correct option is CAREER.

To determine which word cannot be formed using the letters from the word DEMOCRACY, let us first count the available frequency of each letter in DEMOCRACY:
• C: 2
• D: 1
• E: 1
• M: 1
• O: 1
• R: 1
• A: 1
• Y: 1

Now, let us analyze the options:
1. READY: Uses R (1), E (1), A (1), D (1), Y (1). All letters are available in DEMOCRACY.
2. CORE: Uses C (1), O (1), R (1), E (1). All letters are available in DEMOCRACY.
3. MAYOR: Uses M (1), A (1), Y (1), O (1), R (1). All letters are available in DEMOCRACY.
4. CAREER: Requires two 'E's and two 'R's (C-1, A-1, R-2, E-2). However, DEMOCRACY contains only one 'E' and one 'R'.

Therefore, the word CAREER cannot be formed from the word DEMOCRACY.