By refusing to let algernon meet cecily, what character trait does jack display?

Read the passage from The Importance of Being Earnest.

Jack. . . . Old Mr. Thomas Cardew, who adopted me when I was a little boy, made me in his will guardian to his grand-daughter, Miss Cecily Cardew. Cecily, who addresses me as her uncle from motives of respect that you could not possibly appreciate, lives at my place in the country under the charge of her admirable governess, Miss Prism.
Algernon. Where is that place in the country, by the way?
Jack. That is nothing to you, dear boy. You are not going to be invited . . .

By refusing to let Algernon meet Cecily, what character trait does Jack display?

protectiveness
mischievousness
jealousy
compassion

The answer is protectiveness

When does it start and when does it end