The parasympathetic nervous system is involved in

Explanation

The question is asking which of the following options is true about the parasympathetic nervous system. The parasympathetic nervous system is part of the autonomic nervous system, which controls involuntary actions in the body. The options given are A) dilation of the pupil of the eye, B) control the activities of smooth muscles, C) dilatation of the skin, D) controls thinking in mammals, and E) increased metabolism. Option A is incorrect because the sympathetic nervous system is responsible for dilation of the pupil of the eye. Option B is correct because the parasympathetic nervous system controls the activities of smooth muscles, which include the muscles of the digestive system, the urinary system, and the respiratory system. Option C is incorrect because the sympathetic nervous system is responsible for dilatation of the skin. Option D is incorrect because the parasympathetic nervous system is not responsible for controlling thinking in mammals. Option E is incorrect because the parasympathetic nervous system is not responsible for increased metabolism. It is important to note that the sympathetic and parasympathetic nervous systems work together to maintain homeostasis in the body. The sympathetic nervous system is responsible for the fight or flight response, while the parasympathetic nervous system is responsible for the rest and digest response. Both systems are essential for the proper functioning of the body. In conclusion, the correct answer to the question is option B, which states that the parasympathetic nervous system is involved in controlling the activities of smooth muscles.