Answer:
D
Explanation:
The problem given is
![ab+5a-b-5](https://img.qammunity.org/2020/formulas/mathematics/high-school/y1mlfhzl54js2kwp6euat3m3chp5yilfhn.png)
For factoring by grouping, we can "group" first & third terms and then "group" 2nd and 4th term.
![ab+5a-b-5\\=(ab-b)+(5a-5)](https://img.qammunity.org/2020/formulas/mathematics/high-school/3fvd1irk2v12hcx44hfp1euvh88kbw8czx.png)
Note: Then, we find the "common factor" in the first grouping and then find the "common factor" in the next grouping. Then, we simplify.
Since we don't have to factor this, as the problem doesn't demand it, we don't do it.
From our grouping, we see that answer choice D is same. So answer is D.