Hey there!
The answers here are given in a really, really useful formula called point-slope form. It's exactly what it sounds like- you need a point on the line and the slope to write the formula, and from there you can convert it to slope intercept or standard forms.
It's written in this form:
y - y1 = m(x-x1)
Where m means the slope and y1 is the y value and x1 is the x value of the point. You keep the x and y there. That means, with a point of (3, 10) and a slope of 2, we have:
y - 10 = 2(x - 3)
Your answer is B :)
Hope this helps!