The distributive property is the property that a multiplication factor can be distributed into the term of a parenthesis.
This exclude the third option because it don't involve parenthesis.
The other alternatives involve the expression:
[tex]7(x+1)[/tex]Applying the distributive property, we have:
[tex]7(x+1)=7\cdot x+7\cdot1=7x+7[/tex]So, we can see that the alteratives 1 is incorrect because the constant term used was 1. Also, the alternative 4 is incorrect because the coefficient on x is wrong.
The correct alternative is then the second:
[tex]7(x+1)=7x+7[/tex]