During which step does the active player determine which permanents they control will untap?

The active player determines which permanents they control will untap during the Untap step. This is the first step of the turn, and its primary purpose is to return all tapped permanents the player controls to the untapped state. When a turn begins, the active player will untap all of their tapped permanents, with the sole exception of any that specify they do not untap during this step, such as those affected by certain abilities or spells.

The Draw step occurs after the Untap step and is focused on the active player drawing a card. The Beginning of combat step is when players have the opportunity to cast spells or activate abilities that may affect combat. The Declare attackers step is specifically when the active player chooses which of their creatures to declare as attackers.

Understanding the sequence of these steps is crucial for recognizing when certain game actions occur, especially regarding how and when players can enact strategies involving their permanents.