
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
Evaluate the expression $2+4+6+\cdots+398+400 - (3+6+9+\cdots+297+300) - (1+3+5+\cdots+293+295)$.
A) 3146
B) 3050
C) 4000
D) 3200

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