The active player chooses first, followed by each other player in turn order
This is covered by the general rule of APNAP - active player, non-active player. The active player (the player whose turn it is) is the one to make choices first, followed by the other players in turn order. Another example of this rule coming into play would be any card that says "each player sacrifices a creature" - players choose sequentially in turn order, starting with whoever's turn it is, and then after everyone has made their choice, all the chosen creatures get sacrificed simultaneously.
101.4. If multiple players would make choices and/or take actions at the same time, the active player (the player whose turn it is) makes
any choices required, then the next player in turn order (usually the
player seated to the active player’s left) makes any choices required,
followed by the remaining nonactive players in turn order. Then the
actions happen simultaneously. This rule is often referred to as the
“Active Player, Nonactive Player (APNAP) order” rule.