Composers started marking their scores with instructions about dynamics: at the beginning of the 19th centurywell into the 17th centurywell into the 18th centurystarting around the middle of the 16th century answer

The music composers started making their scores with instructions about dynamics only they were well in to the 17th century. Musical dynamics cover all the aspects of it like loudness or softness and the enduring quality which was brought into the music due to the introduction of the new instruments..

The answer is option b and c.