Answer:
a. sham lesion control group.
Step-by-step explanation:
The experimenter will need to conduct a sham or placebo surgery or in simple words a fake surgery or radio frequency lesion on the rats in the control group. This will look like radio frequency lesion to the control group but in actual will be done just to induce the sham or placebo effect for studying the changes in emotional behavior to the lesion. Hence, the experiment will require a sham lesion control group.