Answer:
A.

Explanation:
We have been given a function
and we are asked to find the horizontal asymptote of our given function.
Let us recall the rules for a horizontal asymptote.
- If polynomials of denominator and numerator of a rational function have same degree, then horizontal asymptote will be the quotient of coefficients of the highest degree terms.
- If the polynomial of denominator has larger degree than the numerator, then the horizontal asymptote will be the x-axis or
. - If the polynomial of numerator has larger degree than denominator, then the function has no horizontal asymptote.
First of all let us expand the square given for the denominator.

Now we can see that denominator of our triangle is a second degree polynomial, while numerator is a 1st degree polynomial.
Since denominator has larger degree than numerator, therefore, our function will have a horizontal asymptote at
and option A is the correct choice.