The correct answer is option 'D', which states that all of the sites excavated recently show all three stages of Harappan occupation (pre-Harappan, Harappan, post-Harappan).

Explanation:
The Harappan civilization, also known as the Indus Valley civilization, was one of the most advanced ancient civilizations that flourished in the Indian subcontinent around 2600-1900 BCE. The civilization was characterized by its well-planned cities, advanced drainage systems, and extensive trade networks.

Excavations at various sites have provided valuable insights into the three stages of Harappan occupation, namely pre-Harappan, Harappan, and post-Harappan. Let's examine the three mentioned sites and their significance in understanding these stages:

1. Surkotda:
Excavations at Surkotda, located in Kutch district of Gujarat, have revealed evidence of all three stages of Harappan occupation. The site shows evidence of a pre-Harappan settlement, followed by the development of a Harappan city, and later, evidence of post-Harappan occupation. The discovery of pottery, seals, and other artifacts at Surkotda provides valuable information about the cultural and technological changes that occurred during these stages.

2. Rojdi:
Rojdi, situated in the Rajkot district of Gujarat, is another site where all three stages of Harappan occupation have been identified through excavations. The site exhibits a pre-Harappan phase, followed by the establishment of a Harappan settlement, and subsequent post-Harappan occupation. The discovery of pottery, terracotta figurines, and other artifacts at Rojdi helps archaeologists understand the transition and changes that took place over time.

3. Desalpur:
Desalpur, located in the Kutch district of Gujarat, is yet another site that provides evidence of the three stages of Harappan occupation. Excavations have revealed a pre-Harappan phase, a well-established Harappan settlement, and later, evidence of post-Harappan occupation. The findings at Desalpur, including pottery, beads, and other artifacts, contribute to our understanding of the cultural, social, and economic aspects of the Harappan civilization.

In conclusion, all three mentioned sites, Surkotda, Rojdi, and Desalpur, have been excavated recently and provide evidence of the three stages of Harappan occupation. These excavations have significantly contributed to our understanding of the Harappan civilization and its development over time.