Final answer:
In Fritz Lang's film 'M', the 'monster' metaphorically represents a child murderer and exclusively preys on children, creating a powerful psychological and emotional impact.
Step-by-step explanation:
In the classic film M directed by Fritz Lang, the antagonist, often considered a metaphorical 'monster,' preys exclusively on children. This chilling focus creates a strong emotional impact, similar to the elusive creatures in Alien and Jaws, which also employ a mostly unseen presence to generate suspense and fear. M, however, is notable for its psychological depth and examination of a child murderer in a city gripped by fear and paranoia, which was a groundbreaking narrative at the time of the film's release in the early 1930s.