What is teh use of valid-invalid bit in pagevtable entry?

Question

When the valid – invalid bit is set to valid, it means that the associated page :
a) is in the TLB
b) has data in it
c) is in the process’s logical address space
d) is the system’s physical address space

Answer 1

Option C.

When the valid bit is set then the associated page is in the process's logical address space and the process can use it. If it is not set, then it means that the page page doesn't belong to the current process running.