A thread is usually defined as a "light weight process" because an Operating System (OS) maintains smaller data structures for a thread than for a process. In relation to this, which of the following is TRUE?

A. On per-thread basis, the OS maintains only CPU register state
B. On per-thread basis, the OS does not maintain virtual memory state
C. On per-thread basis, the OS maintains only scheduling and accounting information
D. The OS does not maintain a separate stack for each thread