Which condition is an inflammation of the tissues surrounding the brain and spinal cord? ?

The correct answer is known as "Meningitis"

Meningitis is is an infection of the membranes (meninges) surrounding your brain and spinal cord. The swelling from the illness usually triggers signs which includes headache, fever and a stiff neck. Most cases of meningitis within the U.S. are because of a viral infection, however bacterial and fungal infections are other causes. some cases of meningitis enhance with out remedy in some weeks. Others may be fatal and require immediate antibiotic remedy

Meningitis 

Meningitis is a swelling of the thin sheets/ membranes surrounding the brain and spinal cord which are triggered by common symptoms like stiff neck, headache, and fever. It can be  caused by a virus, bacteria or a fungus. Some improve without treatment but in others, it is deadly.  

C. a mature ovule of a plant.