In the game of Twister, a spinner randomly selects either an arm or a leg, and also selects one of four colors, one of which is
red, each with equal probability, and players have to move the appropriate body part to the appropriately colored spot on the ground. There are four players. Each player spins once, and makes the move the spinner selects. What is the probability that in these four spins, there will be exactly two moves to a red spot, and the body part selected to move will be an arm exactly $3$ times
In agreement to your twister question, a spinner can randomly select whether they want to put an arm or a leg, meaning this choice is entirely upon them. The color choice is also independent, so spinners are allowed to choose freely, whichever color as well as limb they want to move in the game of twister.
See the attached image for step by step explanation of the final probability