The given question provides two statements: an Assertion (A) and a Reason (R). We need to determine the truth value of each statement and whether the Reason correctly explains the Assertion.

1. Assertion (A): Harappan civilization was in close trade relations with South Turkmenistan.
   • The Harappan civilization, part of the larger Indus Valley Civilization, was known for its advanced trade networks. Archaeological evidence suggests that the Harappans engaged in trade with regions as far as Mesopotamia (modern-day Iraq), Iran, and Central Asia, including areas like South Turkmenistan. Hence, the assertion is true.
2. Reason (R): Harappan objects or those produced under Harappan influence have been found at Kish, Ur, Nippur, etc.
   • This statement provides evidence of the widespread trade and cultural influence of the Harappan civilization in Mesopotamian cities like Kish, Ur, and Nippur. These findings demonstrate the Harappan interaction with these regions, corroborating their vast trade networks. Thus, the reason is also true.
3. Evaluating the Explanation:
   • While both the Assertion and Reason are true, the Reason does not specifically explain the Assertion about trade with South Turkmenistan. Instead, it highlights trade with Mesopotamian cities. Therefore, the Reason is not the correct explanation of the Assertion.

Conclusion: Both (A) and (R) are true, but (R) is not the correct explanation of (A).