O Vestigial organs show that whales may have evolved from a common ancestor shared with land-dwelling animals
Explanation:
Vestigial organs are defined as the organs which are no longer beneficial for survival.
Whales can be observed with tiny, unused hip and pelvis bones which are vestigial organs for them as they are no longer beneficial for their survival. The vestigial organs are the evidence of evolution in organisms and in whales also these vestigial organs says that whales and land-dwelling animals may have common ancestors. Later on with evolution some land-dwelling animals might move to water systems and hip and pelvis bones become vestigial organs for them which along with time decreasing in the future offspring.
Hence, the correct answer is "Vestigial organs show that whales may have evolved from a common ancestor shared with land-dwelling animals".
Reforestation is a process of planting trees in an area so as to conserve the land as future forest. According to the given situation, reforestation is the practice which can be used by the biologists to grow nitrogen fixing plants in an area so as to increase the nutrient concentration of the soil which have been depleted.