To rewrite \( x^2 - 196 \) using the polynomial identity \( x^2 - a^2 = (x + a)(x - a) \), we identify \( a^2 \) with 196. This means \( a = 14 \) since \( 14^2 = 196 \).
Thus, we can rewrite \( x^2 - 196 \) as:
\[ x^2 - 196 = x^2 - 14^2 = (x + 14)(x - 14) \]
So the polynomial identity we established is:
\[ x^2 - 196 = (x + 14)(x - 14) \]
Looking through the responses, the correct one is:
\( x^2 - 196 = (x + 14)(x - 14) \).