What is the genus of potato and brinjal?

When writing scientific names by hand,what is drawn under each word?

Assertion $A$: Linnaeus is known as the father of taxonomy.
Reason $R$: Linnaeus classified plants into $24$ groups based on floral characteristics.
Which option is correct for Assertion $A$ and Reason $R$?

Each step of classification represents a:

Which of the following is $NOT$ associated with taxonomy?

Which of the following taxonomic categories contains organisms with the least number of similarities?