During the reign of Emperor Ashoka, which of the following Buddhist missionaries was famously sent to foreign countries such as Sri Lanka in order to preach and spread Buddhism?

Introduction / Context:
Emperor Ashoka is famous not only for adopting Buddhism but also for actively promoting it beyond the borders of his empire. Buddhist sources describe how he sent missionaries to various regions including Sri Lanka, Central Asia and other parts of the Indian Ocean world. This question asks you to identify one of the best known individuals associated with Ashoka overseas missions, especially in relation to Sri Lanka.

Given Data / Assumptions:

• Ashoka is the ruler under discussion.
• The focus is on people sent to foreign countries to preach Buddhism.
• The options include Sanghamitra, Devanampiya, Menander and others.

Concept / Approach:
According to traditional accounts, Ashoka sent his son Mahinda and his daughter Sanghamitra as missionaries to Sri Lanka. These missions helped establish Buddhism in the island kingdom and led to the planting of a branch of the Bodhi tree there. Devanampiya Tissa was the Sri Lankan king who accepted Buddhism, not a missionary. Menander was a later Indo Greek ruler associated with Buddhist dialogues in the Milinda Panha. Among the people listed, Sanghamitra stands out as the missionary actually sent by Ashoka to another country.

Step-by-Step Solution:
Step 1: Recall that Ashoka organised missions led by monks and sometimes by members of his family. Step 2: Remember that tradition names Mahinda and Sanghamitra as envoys to Sri Lanka. Step 3: Identify Sanghamitra in the options and note that she is described explicitly as a missionary. Step 4: Recognise that Devanampiya refers to the Sri Lankan ruler title Devanampiya Tissa, not to a missionary sent by Ashoka. Step 5: Note that Menander was a later Indo Greek ruler associated with Buddhism but not someone sent by Ashoka.

Verification / Alternative check:
A quick way to verify is to recall the famous story that Ashoka daughter Sanghamitra carried a branch of the holy Bodhi tree from Bodh Gaya to Sri Lanka. This story is repeatedly mentioned in exam oriented notes and underlines her role as a missionary. None of the other names in the options have this specific connection to Ashoka missionary policies and the spread of Buddhism beyond India.

Why Other Options Are Wrong:
Option B is wrong because Devanampiya was the royal title of the Sri Lankan king who received the missionaries, not a missionary himself. Option C, Menander, is historically important but belonged to a later period and ruled in North West India and Afghanistan region, not as an envoy of Ashoka. Option D is incorrect because it denies the missionary activity that is a well known feature of Ashoka reign. Option E, Chandragupta, founded the Maurya dynasty but is not associated with Buddhist missions abroad.

Common Pitfalls:
Learners sometimes confuse the names of missionaries with the names of foreign kings involved in the story, such as Devanampiya Tissa. Another pitfall is to think only of Mahinda and forget that the question might pick Sanghamitra instead. To avoid mistakes, remember both names as part of Ashoka Sri Lanka mission and be ready to select either one if it appears in the options with a missionary description.

Final Answer:
Ashoka famously sent Sanghamitra, who travelled to Sri Lanka as a Buddhist missionary, to foreign countries to preach Buddhism.