(a) A career is a profession or occupation that a person pursues over a long period of their life to earn a living and achieve personal and professional growth.
(b) A person can earn a living in two ways:
The source passages provided relate to investment and securities, not careers. The question is from a different chapter/topic (likely an introductory chapter on careers and employment). The answers above reflect standard CBSE Class 10 (Employability Skills / Vocational) definitions:
If your textbook has a specific definition, always prefer that exact wording.