The correct option is C Mimosoideae
Legume is a dehiscent fruit that develops like a follicle and dehisce along two sutures, it is also termed as pod. A modified legume that dehisces along transverse constrictions is termed as lomentum.
Papilionadae has legume fruit with very hard seed coat.
Caesalpinioideae has legume or pod, rarely lomentum.
Mimosoideae has legume or lomentum (mostly) with very hard seed coat. Leguminosae has legume or pod fruit
Therefore, the correct answer is option C.