4.

When the doctor strikes Sofia’s knee with a tool, her leg automatically kicks into the air. What BEST explains this movement?

Sofia’s brain is responding to a stimulus.

Sofia has great reaction time.

Sofia has working reflexes.

Sofia’s body is demonstrating its power.

1 answer

The best explanation for this movement is that Sofia has working reflexes. When the doctor strikes Sofia's knee with a tool, her leg automatically kicks into the air in a reflexive response. Reflexes are involuntary actions that occur in response to certain stimuli, bypassing conscious thought and involving a direct neural pathway from the sensory receptor (in this case, the knee) to the motor neuron (causing the leg to kick).