A comet is a meteoroid that travels through Earth’s atmosphere and hits the surface.

meteoroid that burns up in Earth’s atmosphere, producing a streak of light.

small, rocky object that orbits the Sun and is usually found in a belt between the orbits of Mars and Jupiter.

small object made of ice and dust that orbits the Sun and forms a coma as it approaches the Sun.

D) small object made of ice and dust that orbits the Sun and forms a coma as it approaches the Sun.

the glands which are associated with each description is given below:

pancreas - is an endocrine and exocrine gland that secretes juices with enzymes for digestion. salivary glands- with protection and digestion in the mouth. liver- secretes bile for digestion.   lachrymal glands - secrete tears to moisten eyes and protect them from particles and infection.   sweat gland -regulates water, salt, and temperature. oil glands - to form a protective barrier on the skin.   goblet cells - secrete mucus for protection.