Flatworms are capable of reproducing sexually or by budding fragmentation reverse osmosis

Fragmentation. Flatworm having both male and female organs and asexually by fragmentation. In fragmentation, a new organization is form from the old part which break from the parents. Each piece will become a separate worm.  hope this helps

Fossil found in strata reveal that unused body part decrease in size

The right answer is c.sandstone.