The correct answer is B. Brain and spinal cord
Explanation:
In biology, the nervous tissue is one of the main tissues in the nervous system that is responsible for movement, communication between different parts of the body and perception/processing of information. This tissue can be found mainly in the brain, the spinal cord and the nerves which are also the most important structures in the Nervous system. Also. this tissue includes different types of specialized cells such as the neuroglia cells and neurons. According to this, the largest mass of nervous tissues is found in the brain and spinal cord, because it is in these structures most nervous tissues can be found.
