The standard form of a circle's equation is given by:
\[ (x - h)^2 + (y - k)^2 = r^2 \]
where \((h, k)\) is the center of the circle and \(r\) is the radius.
In this case, the center is \((-2, 0)\) and the radius is \(7\). So, we substitute \(h = -2\), \(k = 0\), and \(r = 7\) into the equation:
\[ (x - (-2))^2 + (y - 0)^2 = 7^2 \]
This simplifies to:
\[ (x + 2)^2 + y^2 = 49 \]
Therefore, the correct equation of the circle in standard form is:
\[ (x + 2)^2 + y^2 = 49 \]
The correct response is:
\((x+2)^2 + y^2 = 49\) (which is the third option).