Which event has a probability other than 1 half ?

A coin has a 1/2 chance of landing tails, and a standard deck has 26 red cards out of 52, also 1/2. A number cube has three even numbers (2, 4, and 6) out of six, so that chance is 1/2 too. The alphabet bag has 5 vowels out of 26 letters, which is not 1/2, so choosing a vowel is the event with a different probability.

AI-written and checked against the verified answer.