Q. Plants of this group are diploid and well adapted to extreme conditions.
They grow bearing sporophylls in compact structures called cones. The group in reference is

 2575  177 Plant Kingdom Report Error

Solution:

The life cycle of gymnosperms have a dominant sporophyte and reduced gametophyte with the female gametophyte retained on the sporophyte. The male and female sex organs are formed in structures called cones or strobili. In gymnosperms both the sexes are separate. Meiosis occurs in both male and female strobili.
So, the correct answer is "Gymnosperms ".