Vectors are added graphically using:

Explanation

(a) Right hand rule: The right hand rule is a rule used in physics to determine the direction of a vector resulting from a cross product. It involves using your right hand and aligning your fingers in a specific way to determine the direction. (b) Left hand rule: The left hand rule is similar to the right hand rule but involves using your left hand instead. It is also used to determine the direction of a vector resulting from a cross product. (c) Head to tail rule: The head to tail rule is a graphical method used to add vectors. It involves placing the head of one vector at the tail of another vector and drawing a vector from the tail of the first vector to the head of the second vector. The resultant vector is the vector that starts from the tail of the first vector and ends at the head of the second vector. (d) Hit and trial rule: The term "hit and trial rule" is not commonly used in the context of vector addition. It may refer to a trial and error method where you try different combinations or approaches until you find the correct solution. In the context of the question, the correct answer is (c) head to tail rule, as it is the graphical method used to add vectors.