The valsalva maneuver involves expiring against a closed glottis and, when combined with contracting muscles of the abdomen and ribcage, creates rigidity in the entire torso. true or false?

Ci want to say is right

I’m going to guess these are the choices: a) recreational skiing developed in the mid-19th century b) it was originally invented as a way of getting from place to place in snowy regions c) downhill skiing is currently the only common form of the sport d) it mostly evolved from snowshoeing- if that’s the cases then the answer would be c) downhill skiing is currently the only common form of the sport