Step 1: Understanding the Question:
This question tests knowledge of transgenic crops in India.
Step 2: Detailed Explanation:
The first transgenic variety developed and commercialized in India was in Rice.
Specifically, Bt rice (insect-resistant rice) was developed in India.
However, Bt brinjal was the first to be approved for commercialization in India in 2009, but it was later put on hold.
The first transgenic variety developed in India was in rice.
Wheat (A): Not commercialized in India.
Pigeon pea (B): Not commercialized.
Cowpea (C): Not commercialized.
Thus, rice is the correct answer.
Step 3: Final Answer:
Thus, the first transgenic variety in India was in rice, which corresponds to option (D).
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