In the galactose utilization system of yeast, the gal4p protein is in the galactose utilization system of yeast, the gal4p protein is a repressor an inducer an activator an enhancer

Based on the given options above, the most probable answer to this question is  an activator. The GAL4  protein is an activator to the galactose utilization system of the yeast Thank you for your question. Please don't hesitate to ask in your queries. 

option b is correct u should go for that