
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
From a regular nonagon, a triangle is formed by connecting three randomly chosen vertices of the nonagon. What is the probability that at least one of the sides of the triangle is also a side of the nonagon?
A) $\frac{5}{14}$
B) $\frac{9}{14}$
C) $\frac{10}{21}$
D) $\frac{2}{3}$
E) $\frac{11}{14}$

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