Answer :

To determine the simplest form among the given expressions, we should inspect each option and see if it can be simplified further.

### Option A: [tex]\(7x - 3\)[/tex]

This expression is already in its simplest form. There are no denominators or additional terms that can be simplified further.

### Option B: [tex]\(\frac{7x - 27}{9}\)[/tex]

To check if this expression can be simplified, we'll look at the numerator [tex]\(7x - 27\)[/tex]. We need to see if it has any common factors with the denominator 9.

However, 7 and 27 do not have a common factor with 9. So, this expression cannot be simplified further.

### Option C: [tex]\(\frac{13x - 27}{9}\)[/tex]

Similarly, for this expression, we look at the numerator [tex]\(13x - 27\)[/tex]. We need to determine if it has any common factors with the denominator 9.

Again, 13 and 27 do not have a common factor with 9. Therefore, this expression cannot be simplified further.

### Option D: [tex]\(\frac{7x - 3}{9}\)[/tex]

To determine if this fraction can be simplified, we consider the numerator [tex]\(7x - 3\)[/tex]. Like in previous cases, we see if it shares any common factors with the denominator 9.

Here, 7 and 3 have no common factors with 9 either. So, this expression is already in its simplest form as well.

### Conclusion

Evaluating the simplest forms of all expressions, we see:

- Option A: [tex]\(7x - 3\)[/tex] is already simplified.
- Option B: [tex]\(\frac{7x - 27}{9}\)[/tex] cannot be simplified further but it's more complex due to the fraction and values.
- Option C: [tex]\(\frac{13x - 27}{9}\)[/tex] cannot be simplified further but it is also a complex fraction.
- Option D: [tex]\(\frac{7x - 3}{9}\)[/tex] is a fraction but again doesn't simplify further.

Considering simplicity in terms of fewer operations and clarity, Option A, [tex]\(7x - 3\)[/tex], is the most straightforward and simplest form.

Thus, the simplest form of the expression is:

Option A: [tex]\(7x - 3\)[/tex].