HELP!!!
what on earth do they want you to do, during the cutscene a large arrow apears and gives you a millisecond to hit a certain button to save Lara from certain death, Which button is it then. Have tried loads of buttons but none seem to do the trick. Am trying to jump up and catch hold of a rope to cross over a pit where loads of stone slabs have fallen from under her feet. She is not jumping high enough and end up hanging from the ledge with one hand then falls

Please help. Am now stuck and cant go any further.