Answer:
Second option:
Explanation:
A quadratic function has the form:

(Where
)
You can observe that the highest exponent of a quadratic function is 2.
Then, let's check which of the options shows a quadratic function:
1)
Its highest exponent is 3, then this is not a quadratic function.
2)
Its highest exponent is 2 and
, then this is a quadratic function.
3)
Its highest exponent is 1, then this is not a quadratic function.
4)
You can observe that
, then this is not a quadratic function.