Answer:
B. Describing their physical strength
Explanation:
Although you have not cited the text to which this question refers (which makes it difficult to elaborate an answer), we can say that the word "aggressiveness" refers to physical behavior, where the strength of an individual is capable of provoking aggression to those who don't have the same strength to defend themselves. In this case, if a narrator wishes to address the aggressiveness of SS officers, he must emphasize their physical strength.
