Final answer:
The cast of Hamlet went through a 'rehearsal' before their main performance, with 'Dress Rehearsals' being the most important as actors practice under showtime conditions, integrating all design and technical elements.
Step-by-step explanation:
The cast of Hamlet had to go through a rehearsal before their main performance. Specifically, they would engage in various stages of rehearsals, including tablework, technical rehearsals, and most importantly, Dress Rehearsals. During Dress Rehearsals, actors practice under showtime conditions, which means the production should look, sound, and feel as if it were the actual performance night. This is vital for integrating all design and technical aspects, such as lights, microphones, sets, and costumes, and any issues must be resolved at this time. The correct answer to the question is therefore c. rehearsal.