What does Lexicology, a brunch of linguistics study?

What is the basis of the traditional and oldest principle for classifying phraseological unit?

1. 
   It is based on their associations.
   
2. 
   It is based on their linguistic characteristics.
   
3. 
   It is based on the semantic principle.
   
4. 
   It is based on their structural characteristics.
   
5. 
   * It is based on their original content.
   

16. 
    There are words which a re avoided because they ....
    

1. 
   are considered too simple.
   
2. 
   are considered delicate.
   
3. 
   *are considered rude and impolite.
   
4. 
   are considered ridiculous.
   
5. 
   are considered funny and foolish.
   

16. 
    How do we call the process of development of a new meaning?
    

1. 
   We term it "similarity".
   
2. 
   *We term it "transference".
   
3. 
   We term it "semantic process".
   

D. We term it "association".

5. 
   We term it "slang".
   

16. 
    Contracted words are produced in two different ways: the first is to make a new word from a syllable of the original word. What is the second?
    

1. 
   to make a new word from the root of the original word.
   
2. 
   to make a new word from the last letters of a word-group.
   
3. 
   to make a new word from the stem of the word.
   
4. 
   *to make a new word from the initial letters of a word group.
   
5. 
   to make a new word from the affixes of the original words.
   

16.