Pointer types: give the correct declaration of t (that is, what is the type of t?). Eg: int k; t = &k;1. int *arr[5]; t = arr[1];2. struct vnode *v; t = &v;3. vaddr_t entrypoint; t = &entrypoint;4. int main(int argc, char **argv) { t = main;5. struct thread ** thr; t = *thr;6. struct thread { ... char *t_name; const void *t_sleepaddr; char *t_stack; ... } struct thread *thr = ... ; t = thr->t_name;希望能给点解释。谢谢