1. **State the problem:** We need to compare $A = n$ and $B = 12$ given the equation $n^{11} = 11^n$.
2. **Analyze the equation:** The equation $n^{11} = 11^n$ means the number $n$ raised to the 11th power equals 11 raised to the $n$th power.
3. **Check if $n=11$ is a solution:** Substitute $n=11$:
$$11^{11} = 11^{11}$$
This is true, so $n=11$ satisfies the equation.
4. **Compare $A$ and $B$ for $n=11$:**
$A = 11$, $B = 12$, so $A < B$.
5. **Check if other $n$ values satisfy the equation:**
- For $n=12$, $12^{11}$ vs $11^{12}$:
Calculate approximate values:
$12^{11} = 743008370688$ (approx)
$11^{12} = 3138428376721$ (approx)
Since $12^{11} < 11^{12}$, $n=12$ is not a solution.
6. **Behavior of the function:**
Define $f(n) = n^{11} - 11^n$.
- At $n=11$, $f(11)=0$.
- At $n=12$, $f(12) < 0$.
- At $n=10$, $10^{11} = 100000000000$, $11^{10} = 25937424601$, so $f(10) > 0$.
This suggests $n=11$ is the only integer solution.
7. **Conclusion:** Since $n=11$ satisfies the equation and $A = n = 11 < 12 = B$, the answer is option (a) $A$.
**Final answer:** a) A
Compare N 12 5E8545
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