Your question is incomplete, in the complete version, Vita was complaining that Helen was flirting with the boys so shamelessly.
Answer:
b. Helen's flirtatiousness and attention to boys was just like Helen of Troy
Explanation:
Because Helen was flirting with the boys so her mum compared her to Helen of Troy.
From the story of Troy, Helen was the wife of King Menelaus who eloped with Paris, the great warrior, Hector's brother.
Because of the insult of having his wife run away from him to a younger lover, a long and bitter war which lasted three years was fought between the two kingdoms.