Complex sentence: The transition of Caitlyn Jenner refers to the coming out of the American athlete formerly known as Bruce Jenner as a trans woman, making her one of the world's most recognized LGBT people.
Split into simpler sentences: The transition of Caitlyn Jenner refers to the coming out of the American athlete formerly known as Bruce Jenner as a trans woman. Her transition made Jenner one of the world's most recognized LGBT people.