Understanding texts with difficult words can be made easier by a study of all except entomology.
Entomology is a branch of zoology. It focuses on the study of insects.
The other options present expressions that would be useful for understanding difficult words:
Affix is an element that we add to a word in order to change its meaning. It may be added to the beginning or the ending of the word.
Etymology is the study of the origin of a word.
Root words are those words that originate other words. For instance, the word "illegal" is originated from the word "legal".
