Sure! Here are the best answers for each question in the passage:

**Question 13:** The best option is **B. are interested**.
The sentence would read: "The students who **are interested** in participating can give their names."

**Question 14:** The best option is **A. compete**.
The sentence would read: "The students who perform the most excellently will be chosen to **compete** in the interschool sports event in our town."

**Question 15:** The best option is **A. Should**.
The sentence would read: "**Should** you have any questions, please contact me via email: sportseventND@gmail.com."

So the final completed passage would be:

"The students who **are interested** in participating can give their names. Various sport events will be held like badminton, basketball, races…The students who perform the most excellently will be chosen to **compete** in the interschool sports event in our town. **Should** you have any questions, please contact me via email: sportseventND@gmail.com."