Answer:
The correct option is D) Birds descended from the most recent common ancestor of reptiles.
Step-by-step explanation:
The modern system of classification is based on the evolutionary history of organisms. The organisms having more common ancestors from the past stand more closely together in the evolutionary tree. The evolutionary history of the birds showed that birds originated from an ancestor which was a reptile in the past. Hence, in the modern system of classification, birds are placed as members of the clade reptiles.