The correct option is
C 35 gm
The spinal cord is a bundle of nerves that connects the brain to other parts of the body. It is located in the vertebral canal of the vertebral column. It is about 45 cm long and about 35gm in weight. It is tubular, slightly flattened anteroposteriorly and has cervical and lumbar enlargements. Its cavity is surrounded by grey and white matter.
Thus, the correct answer is D.