The logical answer is c provided that the "new, better idea" stand up to scrutiny under the scientific method.
Politics (b.) should never be a reason for changing scientific ideas.
Likewise, the fame of a particular scientist should have nothing to do with the modification of a scientific idea.
Science uses the scientific method and whether people are tired of old ideas or not is not a reason to change them.
What is the question so we can help
It is a dietary supplement that helps generare <span>collagen which </span>repair tissues (oranges are pretty good for your skin basically) protect against heart disease, decreases bad cholesterol and prevents specific diseases.