In the sample space \( S = {a, b, c, d, e, f} \), the vowels are \( {a, e} \), while the consonants are \( {b, c, d, f} \).
There are 4 consonants (b, c, d, f) out of a total of 6 letters in the sample space.
To find the probability of picking a consonant, we can use the formula:
\[ P(\text{consonant}) = \frac{\text{Number of consonants}}{\text{Total number of outcomes}} = \frac{4}{6} = \frac{2}{3} \]
So the probability of picking a consonant is:
\[ \frac{2}{3} \]
Therefore, the correct answer is:
\(\frac{2}{3}\) (which corresponds to the third response).