It seems that some information is missing regarding the second and third options for the rational expressions you are inquiring about. However, to determine if a rational expression can be simplified, you typically look for common factors in the numerator and the denominator.
Let's analyze the first option you provided:
Option 1: \( \frac{7x}{5x + 7} \)
This expression cannot be simplified further because there are no common factors between the numerator (7x) and the denominator (5x + 7). The numerator contains the variable x, while the denominator does not have x as a common factor.
If you can provide the second and third options, I would be able to help you further determine which rational expressions can be simplified.