The present Book “DRDO-(STA-’B’)” for Electrical, Electronics and Communication, Electronics and Instrumentation, Electrical and Electronics Engineering is strictly on guidelines laid down by “Defence Research and Development Organization (DRDO), Ministry of Defence Centre for Personnel Talent Management (CEPTAM).” The book is written in a very Simple and Lucid Manner. The book is subdivided into three main sections : (a) General Awareness and Reasoning (b) Electrical and (c) Electronics and Communications ; Electronics and Instrumentation ; Electrical and Electronics Engineering. The book has been prepared to enable readers to face Entrance Tests for other Organisation like BSNL, DMRC etc.