I am pretty sure it is A because you could use a test tube or beaker filled with water and turn it upside down in another container filled with water and then use a hose or something to let the gas into the test tube to displace the water.You can't have use a gas that is soluble in water. am pretty sure it is A because you could use a test tube or beaker filled with water and turn it upside down in another container filled with water and then use a hose or something to let the gas into the test tube to displace the water.
verb (used with object), preserved, preserving. 1. to keep alive or in existence; make lasting: to preserve our liberties as free citizens. 2. to keep safe from harm or injury; protect or spare. 3. to keep up; maintain: to preserve historical monuments.
Meaning: The activity of protecting something from loss or danger. Classified under: Nouns denoting acts or actions. Synonyms: preservation; saving. Hypernyms (preservation is a kind of...): protection (the activity of protecting someone or something) Hyponyms (each of the following is a kind of preservation): environmentalism (the activity of protecting the environment from pollution or destruction) conservation (the preservation and careful management of the environment and of natural resources)