Final answer:
The meaning of the word ‘sang-froid’ is composure or coolness in difficult situations, which is best represented by the word (1) ‘aplomb’.
Step-by-step explanation:
The word ‘sang-froid’ originates from French and is used in English to denote composure or coolness shown in danger or under trying circumstances. The most appropriate synonym for the word from the options provided is aplomb, which means the ability to remain calm and confident, especially in a high-pressure or difficult situation.
Neither self-confidence (option 2) nor uneasiness or perturbation (options 3 and 4) fully capture the essence of ‘sang-froid’ as aplomb does, since this term emphasizes maintaining one's composure specifically in challenging times.