Ants communicate with chemicals called pheromones.
Pheromones are subtle scents emitted by animals in mating season.
Ants communicate with subtle scents.
What communicates with subtle scents?

[a] bears
[b] viruses
[c] bacteria
[d] Birds
[e] bats
[f] ants
[g] koalas
[h] phytoplankton