To solve the given question, we need to determine which author wrote about the concept of "the enhancement of freedoms that allow people to lead lives that they have reason to live," which is associated with 'Development as Freedom'. The options provided are:
- John Rawls
- Amartya Sen
- Robert Nozick
- Jean Dreze
This concept is rooted in the work of Amartya Sen, a renowned economist and philosopher. His book "Development as Freedom" explores the idea that development should be assessed by the freedoms and capabilities people have, instead of traditional economic metrics like GDP.
Thus, the correct answer is:
Amartya Sen