Agrobacterium infects plants and causes them to form tumors. You are asked to determine how long a plant must be exposed to these bacteria to become infecteWhich of the following experiments will provide the best data to address that question? a. Measure the number of tumors formed on plants, which are exposed to a known concentration of Agrobacterium solution for different lengths of time.
b. Measure the concentration of Agrobacterium in different soil environments where the plants grow.
c. Measure the number of tumors formed on a plant when exposed to various concentrations of
d. Measure the number of tumors formed on plants, which are exposed to different concentrations of an Agrobacterium solution for different lengths of time.