To determine the probability that a randomly selected letter from the English alphabet comes after \( D \) in the alphabet, we can follow these steps:
1. Count the Total Number of Letters in the Alphabet:
The English alphabet has a total of 26 letters.
2. Identify the Position of the Letter \( D \):
\( D \) is the 4th letter in the alphabet.
3. Count the Number of Letters After \( D \):
The letters following \( D \) in the alphabet are \( E, F, G, \ldots, Z \).
These letters comprise the 5th position through the 26th position of the alphabet.
Therefore, the number of letters after \( D \) is \( 26 - 4 = 22 \).
4. Calculate the Probability:
The probability is the ratio of the number of favorable outcomes (letters after \( D \)) to the total number of possible outcomes (all letters in the alphabet).
[tex]\[
\text{Probability} = \frac{\text{Number of letters after D}}{\text{Total number of letters}} = \frac{22}{26}
\][/tex]
5. Simplify the Fraction to Match One of the Provided Answer Choices:
Simplifying \(\frac{22}{26}\):
[tex]\[
\frac{22}{26} = \frac{11}{13}
\][/tex]
None of the provided answer choices are \(\frac{11}{13}\), but using the numerical value derived:
[tex]\[
\approx 0.8461538461538461
\][/tex]
This approximately matches answer choice \( C \).
Therefore, the correct answer is:
[tex]\[
\boxed{\frac{21}{26}}
\][/tex]