Question

Invasion is when

a
b
one group enters the boundaries of another group as an enemy
you invite another group to cross your boundaries
you argue with another group
ос

Answer 1

invasion is when one group enters the boundaries of another group as an enemy

hope this helps , have a nice day ʘ‿ʘ

Answer 2

Invasion would be when one group enters the boundaries of another group as an enemy.