Which part of the plant $Rafflesia$ $arnoldii$ is shown in the given image?

$A$ flower is zygomorphic when:

Among bitter gourd,mustard,brinjal,pumpkin,China rose,lupin,cucumber,sunn hemp,gram,guava,bean,chilli,plum,Petunia,tomato,rose,Withania,potato,onion,Aloe,and tulip,how many plants have hypogynous flowers?

Two spines in $Trapa$ fruit ($Singhara$ fruit) are modifications of

Perianth is the condition in which

In which of the following are the flowers unisexual?