Correct Option: C

moving (Adjective) : in motion
stationary (Adjective) : not moving ; static ; not intended to be moved ; not changing in condition or quantity
slowing (Noun) : a decrease in speed
standing (Adjective) : having a supporting base ; not moving or
flowing (liquids) ; maintaining an erect position
writing (Noun) : the act of creating written words ; the work of a writer