Question

which of the following is not matter?
a sound
b plant
c cloud
d feather

Explanation:

Matter is anything that has mass and takes up space. Plants, clouds (which are made of water droplets or ice crystals), and feathers are all composed of particles with mass and occupy space. Sound, however, is a form of energy (mechanical wave energy) that travels through a medium (like air, water, or solids). It does not have mass and does not occupy space in the way matter does.

Answer:

A. Sound