A chemical substance produced naturally in plants and are translocated to another region for regulating various physiological reactions is known as
Phytochromes
Phytocyanin
Phytohormones
Both b and c
As we learn
Phytohormones -
A chemical substance produced naturally in plants which is translocated to another region for regarding physiological reactions when present in low concentration.
Plant growth promoter - auxins, gibberellins and cytokinines Plant growth inhibitor - ABA, ethylene. Hence the correct option is c.