ANS:D - all of these.

The check line is also known as proof line..it is used to check the accuracy of survey lines. and A"tie line" is that line which joins some fixed points called "stations" on the main survey lines. The purpose of a tie line is two-fold, i.e., firstly it enables checking of the accuracy of the network and secondly locating the interior details which are comparatively far away from the main survey lines.