QUESTION 1 The multithreading model multiplexes one user-level thread to one kernel thread. O A. one-to-one model . many-to-some model OC. many-to-one model O D.many-to-many model QUESTION 2 Pthreads refers to O A a specification for thread behavior. . an implementation for thread behavior. OC. the POSTFIX standard. O D. an API for process creation and synchronization, QUESTION 3 Windows 10 uses the O A. one-to many-model OB. many-to-one model OC. many-to-many model O D.one-to-one model QUESTION 4 The model maps many user-level threads to one kernel thread. A. one-to-one OB. many-to-one O C. two-level O D. many-to-many