The two lobes of the brain that play a significant role in processing smells, such as picking out the scent of a rose in a mixed bouquet, are the frontal lobe and the temporal lobe. The olfactory bulb, which is involved in the sense of smell, is anatomically linked to the frontal lobe, while the temporal lobe also contains structures involved in the processing of olfactory information.
So, the correct answer is frontal and temporal.