Which one of the following microbial agents is being commercially exploited as biocontrol agent

Trichoderma viride is the microbial agents that that is being commercially exploited as biocontrol agent.
Trichoderma viride is a fungus and a biofungicide. It is used for seed- and soil treatment for suppression of various diseases caused by fungal pathogens.
The fungicidal activity makes T. viride useful as a biological control against plant pathogenic fungi. It has been shown to provide protection against such pathogens as Rhizoctonia, Pythium and even Armillaria.