To determine: The correct option.
The correct option is (d) 4.
In the head-tail arrangement of the vector diagram, the resultant vector is drawn from the tail of the first vector to the head of the second vector , for the convenience of the calculation of the magnitude of the resultant using the Pythagoras theorem or the expression for finding the resultant vector,
A is the magnitude of the vector , and
B is the magnitude of the vector .
So, the correct option is (d) which the exact head-tail arrangement of the vectors.
Thus, the correct option is (d) 4.