answer question NBME please - casanova

[ArchivalUser]

A sexually active 18 year old woman comes to the physician's office b/c of fever, lower abdominal pain and a purulent vaginal discharge for the last 3 weeks. A tender mass is palpated in the right lower quadrant on bimanual exam. Which of the following is the most likely site of the mass?
a. ovary
b. fallopian tube
c. uterine fundus
d. uterine body
e. vagina
f. bladder
g. rectum

[ArchivalUser]

PID, the answer is B) Fallopian tube

[ArchivalUser]

I heard it can be the ovary.
Can you give me more explaination about that