Final answer:
The cause of acute aseptic meningitis in the options provided is C. Herpes simplex virus. Aseptic meningitis is often less severe than bacterial meningitis and typically does not present with bacterial growth in the cerebrospinal fluid cultures.
Step-by-step explanation:
A cause of acute aseptic meningitis is C. Herpes simplex virus. Aseptic meningitis can be caused by a variety of factors, including viruses, and is characterized by the lack of growth of bacteria in cultures of the cerebrospinal fluid. Among the viruses that can cause aseptic meningitis, the Herpes simplex virus is a well-known cause. Bacterial meningitis, on the other hand, is caused by bacterial infections and can be more severe. Bacteria that are commonly associated with bacterial meningitis include Neisseria meningitidis, Haemophilus influenzae, Streptococcus pneumoniae, and Streptococcus agalactiae (group B streptococci). These bacteria can invade the central nervous system, leading to inflammation of the meninges and symptoms such as fever, neck stiffness, and confusion.