Step 1: Understanding the Concept:
The year 78 CE marks the beginning of a significant era in Indian history, known as the Saka Era. This era is associated with the accession of a major ruler from the Kushan dynasty.
Step 2: Detailed Explanation:
The year 78 CE is widely accepted by historians as the year of accession of the Kushan emperor Kanishka the Great. This year marks the beginning of the Saka Era, which was adopted as the basis for the Indian national calendar in 1957.
Let's analyze the other options:
(A) Beginning of Gupta rule: The Gupta Empire was founded by Sri Gupta, but the era of Gupta dominance began with Chandragupta I in c. 320 CE.
(C) End of the Mauryan Empire: The Mauryan Empire ended around 185 BCE with the assassination of the last emperor, Brihadratha.
(D) Reign of Ashoka: Ashoka the Great, a Mauryan emperor, reigned in the 3rd century BCE (c. 268–232 BCE).
Thus, 78 CE is directly related to the reign of Kanishka.
Step 3: Final Answer:
The year 78 CE corresponds to the beginning of Kanishka's reign and the start of the Saka Era. Therefore, option (B) is the correct answer.