The series is widely used in Pakistani schools and universities, consisting of multiple volumes. You can find digital copies of the textbooks themselves on Archive.org to compare with your answers. Muallim-ul-Quran Answer Key PDF - Scribd
Here is how you can find the answer key, depending on which specific book you are using: muallim ul quran answer key
Muallim-ul-Quran BS-09 Answer Key : A specific key for a 100-question examination related to the Muallim-ul-Quran curriculum used by certain institutions. The series is widely used in Pakistani schools
If you are using the standard color-coded Qaida often used in Pakistan and India (usually by Prof. Abdul Rehman Tahir): muallim ul quran answer key