Although there is an urgent need for better new drugs to treat neurodegenerative diseases, for large pharmaceutical companies, the development of related drugs is too complicated and expensive, and R & D that costs millions of dollars may fail at any time and the investment risk is huge. Count on large pharmaceutical companies to invest in drugs that treat neurodegenerative diseases. Which of the following is true and can best refute the above reasoning? ? ['most neurodegenerative diseases are not contagious, and the harm to life is slow and long-term.', 'The cost and complexity of cancer drug research and development is the highest of all drug developments, but many large pharmaceutical companies are still investing heavily in this.', 'although some neurodegenerative diseases can be treated by non-drug methods, the treatment is very cruel and it is easy to cause permanent damage to patients.', 'the average drug development cycle only takes 1.2 years, while the neurodegenerative drug development cycle takes 6 to 10 years.']