Answer:
Team A exert more force on ground.
Step-by-step explanation:
In Tug of war since both teams are pulling two ends of a string or rope so here the net force on the string along with two teams would be zero
So in order to win the game each team has to exert force on the ground.
When team exert more force on the ground then due to the reaction force of ground on the team in opposite direction will help the team to pull the rope towards them
So here if Team A wins the game then the force exerted by that team on the ground must be more due to which the reaction force by ground on the team is of larger magnitude and hence they wins the game