Which of the following is NOT an example of an organ system?

a. sensory

b. circulatory

c. respiratory

d. digestive

The correct answer is option A, sensory system.

A human body primarily consists of the following organ systems:

Circulatory, Respiratory, Digestive, Excretory, Nervous and Endocrine systems, Immune, Integumentary, Skeletal, Muscle and Reproductive systems.

There is no as such sensory system. However the neurology based system is called Nervous system which includes organs and their processing in the sensing of stimulation.