We know,\\\\(\\displaystyle pH = \\dfrac {1}{2} (pK_w+pK_a -pK_b)\\\\)\\\\(\\displaystyle pH = \\dfrac {1}{2} (14+3.2-3.4)\\\\)\\\\(\\displaystyle pH= \\dfrac {1}{2}(13.8)\\\\)\\\\(\\displaystyle pH=6.9\\\\)Hence, the option (A) is the correct answer.