Suppose if RAM of capacity 64 or 128 MB to be used by the CPU resources. This amount of RAM is not sufficient to run all applications that are used by most users in their expected way and all at once. For example, an e-mail program, a web browser and a word processor is loaded into RAM simultaneously; the 64 MB space is not enough to store all these programs. In the absence of virtual memory, a message “Sorry, you cannot load any more applications. Please close an application to load a new one.” would be displayed. With the use of virtual memory, a computer can look for empty areas of RAM which is not being used currently and copies them on to the hard disk device. This process frees up RAM to load new applications. As it is done automatically, the user do not even know that it is happening, and the user feels like RAM has unlimited space even though the RAM capacity is 32 MB. The fact that hard disk space is much cheaper than RAM chips allows virtual memory also as a nice economic benefit. So, option A, is the best option.