Through the study of classification,which of the following is true?

Into how many groups did Linnaeus classify plants based on sexual characteristics?

Ernst Mayr's biological concept of species is mainly based on:

$Nicotiana \ sylvestris$ flowers only during long days and $N. \ tabacum$ flowers only during short days. If raised in the laboratory under different photoperiods,they can be induced to flower at the same time and can be cross-fertilized to produce self-fertile offspring. What is the best reason for considering $N. \ sylvestris$ and $N. \ tabacum$ to be separate species?

Common names of some animals are given in Column-$I$. Write their scientific names in Column-$II$.

Column-$I$	Column-$II$
$(A)$ Tiger	...........
$(B)$ Peacock	...........
$(C)$ Housefly	...........

To indicate their Latin origin,scientific names are printed in which style?