Answer:
B.

Explanation:
Let's use the slope equation first. The slope equation is as follows:

This is what is given in the equation:
Let's label each component of the equation using these points:
y2 = 9
y1 = 7
x2 = 6
x1 = 3
Now, plug these into the equation

We can now eliminate A and C of the answer choices.
Now let's find the y intercept
Right now we have the following equation

In order to find the y intercept we need to plug in one of the given points into the equation. Let's use point (3,7).
The equation should look like this now:

Now lets solve for the y-intercept

Now that we found the y-intercept is 5 we have our full equation!

Hope this helps!!
- Kay