Final answer:
The Frontal Lobe is responsible for complex cognitive functions such as reasoning, planning, speech, movement, emotions, and problem solving.
Step-by-step explanation:
The structure that is associated with reasoning, planning, parts of speech, movement, emotions, and problem solving is the Frontal Lobe (Option C). The frontal lobe is located at the front part of the brain, extending back to a fissure known as the central sulcus. It is involved in various cognitive functions, including motor control through the motor cortex, language through Broca's area, and complex cognitive behaviors such as reasoning and problem solving in the prefrontal cortex. It also plays a role in processing emotions.