What event is most likely to happen

A. Getting a 6 when rolling a single dice once
B. Getting a head from a single toss of a fair coin
C. Randomly picking a vowel letter from the English alphabet
D. Randomly picking a consonant from the English alphabet

B. Getting a head from a single toss of a fair coin

This event has a 50% chance of happening, as there are only two possible outcomes (heads or tails) when flipping a fair coin. The other events, such as rolling a 6 on a single dice, randomly picking a vowel letter, and randomly picking a consonant, have lower probabilities of occurring.