The correct answer is option 3 Concept: Multiple threads of the same process share other resources of the process except for register, stack, and stack pointer. In particular, a process is generally considered to consist of a set of threads sharing an address space, heap, static data, code segments, and file descriptors. [ alt="F1 R.S Pallavi 3.12.19 D 5" src="//storage.googleapis.com/tb-img/production/19/12/F1_R.S_Pallavi_3.12.19_D%205.png" style="width: 549px; height: 277px;"> Thread of the same process doesn't share program counter (register), stack, registers Option 1: FALSE On a per-thread basis, the OS maintains only the CPU register state → Incorrect statement Because in the above figure not only CPU register maintained by OS but also maintained code, data, files, stack. Option 2: FALSE The OS does not maintain a separate stack for each thread → Incorrect statement Because OS maintained a separate stack for each thread as shown in the above figure Option 3: TRUE On a per-thread basis, the OS does not maintain a virtual memory state → Correct statement Because OS does not maintain a virtual memory state for an individual thread So, it is a true statement. Option 4: FALSE On a per-thread basis, the OS maintains only scheduling and accounting information → Incorrect statement Because OS maintains not only scheduling and accounting information but also maintained code, data, files, stack.