What are the major challenger of youth felling in 21st century​

By comparing part 1 and 2 of polar opposites what does it mean by polar opposites

The room was gaudy with its leather couch and purple walls

Read the following entries from the online etymology dictionary based on the information above, what does the world microcephaly most likely mean? a. dull or unintelligent b. worldly thinking c. having a large head d. bigger than usual