Dehydration synthesis leads to formation of
monomers
polymers
water and polymers
none of the above

Water and polymers.

Explanation:

Dehydration reaction may be defined as the reaction in which a water molecule is released during the process of reaction. Large molecules are joined together by the process of dehydration.

Polymers are formed by reacting the monomers together with a release of small molecules like water. Hence, water and polymers are formed by dehydration reaction.

Thus, the correct answer is option (3).  

air enters through the nose, moves through the nasal cavity, the pharynx, the larynx, enters the trachea, moves through the bronchi andbronchioles till the alveoli.