
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
For every $n$, the sum of $n$ terms of an arithmetic progression is $4n + 5n^2$. What is the $r$th term of this arithmetic sequence?
A) $10r + 1$
B) $10r - 1$
C) $5r + 5$
D) $5r^2 + 4r$

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