The answer to this is letter B. if you can observe a baby, take a look at the things that the baby does since birth. There are just some things that are involuntary. These are methods that the body does from the very beginning. It can be hard if people would not blink as it can make their eyes dry.
Coughing is the body’s natural method of relieving itchy throat and can also be effective in removing excess water if in case it goes through the windpipe.
Swallowing is another thing that the body does naturally and from the time that the baby starts to breastfeed, the baby will start swallowing the milk and eventually, the food that will be consumed. Gagging is another natural defense of the body. The other options contain things that only babies do; or steps that will only be learned by the baby later on.
Option B - Blink, cough, sneeze and gag.
Blink, cough, sneeze, gag and swallowing are present at birth and they remain unchanged all through adulthood.
Rooting and stepping disappear gradually as the baby grows. Before age 1 these birth reflexes disappear.