The correct answer is: A. It terminates with a solution when one exists.
An algorithm is complete if it always terminates with a solution, if one exists. In other words, it will always stop running and give you an answer, even if that answer is “no solution
exists.”Option B is incorrect because an algorithm does not need to start with a solution. It can start with any input and still be complete if it always terminates with a solution.
Option C is incorrect because an algorithm can terminate without finding a solution. In this case, it is said to have “failed to find a solution.”
Option D is incorrect because an algorithm does not need to have a loop to be complete. A loop is simply a construct that allows an algorithm to repeat itself. It is not necessary for an algorithm to be complete.