A speaks truth 75%
That is,
P(A) = 3/4
\(\begin{array}{l}P(\bar{A})=\frac{1}{4}\end{array} \)
Similarly,
B speaks truth 80%
That is,
P(B) = 4/5
\(\begin{array}{l}P(\bar{B})=\frac{1}{5}\end{array} \)
While contradicting the narration
\(\begin{array}{l}Probability = P(A)P(\bar{B})+P(\bar{A})P(B)\end{array} \)
On substituting, we get,
= (3/4) (1/5) + (1/4) (4/5)
= 7/20
= 7/20 x 100%
We get,
= 35%
Hence, the correct answer is option (c)