What is the sum of real roots of the equation $x^4-7x^3+14x^2-14x+4=0$?

$ \textbf{(A)}\ 1 \qquad \textbf{(B)}\ 2 \qquad \textbf{(C)}\ 3 \qquad \textbf{(D)}\ 4 \qquad \textbf{(E)}\ 5$
1. **Factor the polynomial**: We start with the polynomial equation \(x^4 - 7x^3 + 14x^2 - 14x + 4 = 0\). We are given that it can be factored as \((x^2 - 5x + 2)(x^2 - 2x + 2) = 0\).

2. **Solve each quadratic equation**:
   - For the first quadratic equation \(x^2 - 5x + 2 = 0\):
     \[
     x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}
     \]
     Here, \(a = 1\), \(b = -5\), and \(c = 2\):
     \[
     x = \frac{5 \pm \sqrt{25 - 8}}{2} = \frac{5 \pm \sqrt{17}}{2}
     \]
     The roots are:
     \[
     x_1 = \frac{5 + \sqrt{17}}{2}, \quad x_2 = \frac{5 - \sqrt{17}}{2}
     \]

   - For the second quadratic equation \(x^2 - 2x + 2 = 0\):
     \[
     x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}
     \]
     Here, \(a = 1\), \(b = -2\), and \(c = 2\):
     \[
     x = \frac{2 \pm \sqrt{4 - 8}}{2} = \frac{2 \pm \sqrt{-4}}{2} = \frac{2 \pm 2i}{2} = 1 \pm i
     \]
     The roots are:
     \[
     x_3 = 1 + i, \quad x_4 = 1 - i
     \]

3. **Identify the real roots**: From the solutions above, the real roots are \(\frac{5 + \sqrt{17}}{2}\) and \(\frac{5 - \sqrt{17}}{2}\).

4. **Sum the real roots**: The sum of the real roots is:
   \[
   \frac{5 + \sqrt{17}}{2} + \frac{5 - \sqrt{17}}{2} = \frac{(5 + \sqrt{17}) + (5 - \sqrt{17})}{2} = \frac{10}{2} = 5
   \]

Conclusion:
\[
\boxed{5}
\]