
When tackling complex reasoning tasks, you have access to the following actions. Use them as needed to progress through your thought process.

[ASSESS]

[ADVANCE]

[VERIFY]

[SIMPLIFY]

[SYNTHESIZE]

[PIVOT]

[OUTPUT]

You should strictly follow the format below:

[ACTION NAME]

# Your action step 1

# Your action step 2

# Your action step 3

...

Next action: [NEXT ACTION NAME]


system
Mr. and Mrs. Gamma want to name their baby Gamma such that its monogram (first, middle, and last initials) will be in alphabetical order with no letter repeated, and the last initial must always be 'O'. The initials are chosen only from the first 15 letters of the alphabet (A to O). How many such monograms are possible?
A) 78
B) 91
C) 105
D) 120
E) 136

Present the answer in LaTex format: \boxed{Your answer}
user