The first book on Public Administration was written by:

Public Administration emerged as a distinct academic discipline in the early 20th century, seeking to apply scientific principles to government management. The foundational text that solidified its status as a field of study is widely attributed to L.D. White.

• L.D. White (A), specifically Leonard D. White, published his seminal work, Introduction to the Study of Public Administration, in 1926. This book is universally recognized as the first comprehensive textbook in the field, systematically outlining its scope, principles, and methods, thereby establishing public administration as an independent academic discipline.
• Pfiffner and Presthus (B) were later influential scholars, but not the authors of the first textbook.
• Simon, Smithburg and Thompson (C) co-authored Public Administration in 1950, a highly significant work, but it appeared much later than White's pioneering effort.
• E.N. Gladden (D) was a British scholar who also contributed to public administration literature, but his works did not precede White's foundational text.

Thus, White's 1926 book laid the groundwork for the systematic study of public administration.