Swap space is a space allocated to handle additional programs running when your RAM memory is full.

Let’s say that you have 4 GBs of RAM on your computer, and that 3 programs are already taking 3.5 GBs out of the 4 available.

If you are trying to run a program that is taking 1 GB on normal usage, you won’t be able to do it as you don’t have the space necessary for the program.You could buy some RAM (which is expensive), or you could choose to create some swap space on your host.

When running your 1 GB program, your operating system (Linux here) will “move” or “swap” one of the programs to a dedicated part of your hard drive (your swap partition) and run your 1 GB program on the newly allocated space.

*This Content is collected from https://devconnected.com/

Swap Space এর জন্য যেহেতু Hard Disk - এ স্পেস প্রয়োজন এবং Hard Disk এক ধরনের Secondary Memory, তাই প্রশ্নে উল্লেখিত অপশন গুলোর মধ্যে উত্তর হবে Secondary Memory.