To answer this question, let's go through each option to understand why it is correct or incorrect:
Option A) The LINK is always more efficient than the XCTL. - This option is incorrect. The efficiency of LINK and XCTL depends on the specific scenario and requirements. Both LINK and XCTL have their own advantages and disadvantages, and the choice between them depends on the specific use case.
Option B) LINK returns to the calling program and XCTL will not. - This option is correct. The key difference between LINK and XCTL is that LINK allows the control to return to the calling program after executing the called program or subroutine, while XCTL does not return control to the calling program. After executing XCTL, the control is transferred directly to the called program or subroutine.
Option C) The LINK is not available in the current CICS version. - This option is incorrect. LINK is a standard CICS command and is available in all versions of CICS.
Option D) Link cannot pass values to a subroutine. - This option is incorrect. LINK can pass values to a subroutine using the COMMAREA parameter. The COMMAREA is a data area that can be used to pass data between programs during a LINK operation.
The correct answer is B. LINK returns to the calling program and XCTL will not.