Concept:A body at rest has zero net force, meaning the forces on it are balanced.Solution:The book is at rest on a table.The downward force is its weight, and the upward force is the normal reaction from the table.These two forces are equal in size and opposite in direction, so the net force is zero.Therefore, the net force acting on the book is balanced.Key point: A body at rest or moving with constant velocity has balanced forces (Newton's first law). An unbalanced force would make the book accelerate.Answer:Option A (is balanced)