The following excerpt is adapted from Frankenstein by Mary Shelley. In the novel, the protagonist describes his stepsister, Elizabeth.
Her imagination was luxuriant, yet her capability of application was great. Her person was the image of her mind; her hazel eyes, although as lively as a bird’s, possessed an attractive softness. Her figure was light and airy; and, though capable of enduring great fatigue, she appeared the most fragile creature in the world. While I admired her understanding and fancy, I loved to tend on her, as I should on a favourite animal; and I never saw so much grace both of person and mind united to so little pretension.
Based on the context of the passage, which of the following is the most logical meaning of the word fragile?