A Business Analyst is the one who analyzes the business of an organization. The core duty of a Business Analyst is requirements management.

BA should be able to understand the business policies, business operations, a structure of an organization and suggests any improvements (like how to improve the quality of services, technical solutions to business problems etc) to achieve the goals of an organization.

Business Analyst Interview Questions and Answers
Business Analyst Interview Questions & Answers
Business Analyst Interview Q and A
Business Analyst Interview Q & A