Sports Player, Professional Athlete
Noun
せんしゅ
あのハンサムな選手はだれですか。
Who is that handsome pro athlete?
最近、日本人のプロ野球選手がメジャーリーグでもプレイするすがたがよく見られます。
These days, we can often see Japanese professional baseball players play in the major leagues.
コウイチは素晴らしい剣道の選手です。
Koichi is magnificent pro kendo player.
Remember that 手 can refer a "person" in some words? Well this is one of them. In this case, we have choose person, or perhaps a better way to think of it is like "chosen person." One situation in which you'd choose a person to do something is in sports, like in a schoolyard pick. Keep that in mind and you should be able to remember that this means pro athlete or sports player.
The reading for 選 is what you'd expect. 手 is the on'yomi reading as it is every once in a while, especially when it has to do with representing a person, so you'll have to remember that. I think you've seen 手 using this reading enough to be able to remember it, though.