
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
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Consider a square $\square B_1B_2B_3B_4$ and let $B_{n+4}$ be the point dividing the segment $B_nB_{n+1}$ in the ratio 1:3 (closer to $B_n$) for all positive integers $n$. Compute the angle $\angle B_{43}B_{44}B_{45}$.

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A) $30^\circ$  
B) $45^\circ$  
C) $60^\circ$  
D) $90^\circ$  
E) $120^\circ$

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