In elephants,the tusks are modified:

Which one of the following figures represents the placentation in Dianthus?

Which of the following is a characteristic of monocots?

$S$ Statement: Amorphophallus (Elephant foot yam) has a large inflorescence of about $6 \ m$ height.
$R$ Statement: Rafflesia arnoldii has the largest flower with a weight of about $8 \ kg$ and a diameter of about $1 \ m$.

Which of the following is not true regarding hydrophytes?

According to the classification system of Bentham and Hooker,what is the total number of families of seed-bearing plants (Phanerogams)?