For the given question, we will use the following rule of conditional probability:
[tex]\begin{gathered} P(M\text{ }and\text{ }N)=P(M)*P(N|M) \\ \\ So,\text{ }P(N|M)=\frac{P(M\text{ }and\text{ }N)}{P(M)} \end{gathered}[/tex]
We need to find P(liberal | State B)
Let N = liberal, and M = state B
So, the total number of voters from state B = 35
And the number of voters is liberal from state B = 21
So, the probability will be as follows:
[tex]P(liberal|StateB)=\frac{21}{35}=0.6[/tex]
So, the answer will be option 4) 0.6