Given the limit .
Since the denominator as , and the numerator .
If , we can directly substitute into the expression because it's a rational function and the denominator is not zero at (unless ).
Case 1: .
Substitute :
.
So, we have .
This gives . This is not among the options. Let's recheck the problem statement. It's possible the expression is intended for L'Hopital's rule or factorization where is a factor of the numerator.
.
So, .
If , we can cancel :
The expression simplifies to .
Now take the limit as :
.
So, we have , which gives .
This still leads to the same result, which is not in the options. Is there a typo in the question? Perhaps it was ?
If , this is of the form 0/0, so we can use L'Hopital's rule or factorization.
Using factorization: .
If , then . Still not matching options. Let's check if the question was . Not this form.
What if the limit was ?
Then . No. Let's assume the given limit and equation is correct, but the options are for a different problem that results in integer 'a'.
If the options (a,b,c,d) are for 'a', then would be .
If , then the limit should be 1. But limit is 7.
If , then limit should be 4. But limit is 7. There seems to be a fundamental mismatch between the limit calculation and the provided options.
Let's assume the limit calculation is correct.
However, if we must choose from the options, and option (c) is marked correct.
If , then .
For the limit to be 1, but it is given as 7.
So, the problem statement combined with the options being values for such that does not work with the derived . Could the question have been ?
If the original limit leads to , then the options are incorrect.
If one of the options for is correct, then the limit value 7 is incorrect for this expression.
Example: If , limit value is .
If , limit value is .
If , the limit expression evaluated at gives .
So . .
The checkmark is on option (c) . This would imply that the given limit should have evaluated to 1, i.e., if .
If the equation was , and this result was given as 7. The problem statement has an inconsistency with the options if interpreted directly.
Assume the question intended a scenario where is the answer.
If , then . This should be 7.
If , then . This should be 7.
So, the marked answer (c) does not satisfy the condition that the limit is 7. There is a high probability of error in the question itself (the limit value or the expression) or the options/marked answer.
I must assume the process: . So .
The options are for . If , then .
If the question meant and then something else.
Given the high level of inconsistency, I cannot provide a rigorous step to the marked option (c).
However, if the question was: .
My derivation of the limit being is correct. So . The options are for .
This implies the numerical value "7" in the question or the options for "a" are incorrect.
If we assume option (c) is correct, then . So the limit should have been 1, not 7.