The 'Shepherd's purse' plant is associated with which family?

Which of the following characters are related to the family $Malvaceae$?
$(a)$ Five stamens
$(b)$ Marginal placentation
$(c)$ Infinite stamens
$(d)$ Twisted aestivation

Monadelphous condition is found in .........

The primitive type of stamens are found in the flowers of which family?

Statement $S$: Lemon is an example of Disciflorae.
Statement $R$: In lemon,the thalamus is cup-shaped.

Flowers with monadelphous condition and pentacarpellary ovary are present in