Is matter in the plasma state is the most common on Earth?
No. Plasma is the most common state of matter for the universe, but not the Earth.
There are four types of matter in the universe - solid, liquid, gas, and plasma. Plasma is basically a soup of gases that have been stripped of some of their electrons, either at extremely high or low temperatures. These ionized gases at high temperatures are found everywhere in the universe in the form of stars - and that is why it is the most common form of matter in the Universe. The Earth, on the other hand, is just a combination of solids (The crust and mantle), liquids (The inner core and the oceans), and gases (Our atmosphere).