A scientist has been working for 15 years to develop a new type of plastic material, but she has not yet been successful. Which of the following best explains why her work is still a success? A: New ideas often develop from unsuccessful experimentation.
B: The original problem was not solved and can now be abandoned.
C: Most scientists require several decades of experimenting before achieving their goals.
D: Scientist has demonstrated that there are no new plastics for scientists to develop.