Step 1: Understanding the Concept:
Mutation breeding is a highly effective tool for crop improvement in floriculture.
Because many ornamental crops are highly heterozygous and propagated vegetatively, induced mutations can create novel flower colors, shapes, or growth habits without altering the rest of the plant's genome.
Step 2: Detailed Explanation:
Let us analyze the listed chrysanthemum cultivars:
(A) Birbal Sahni:
This is a famous white, small-flowered pompon cultivar developed at the National Botanical Research Institute (NBRI) in Lucknow, India, through gamma irradiation (induced mutation).
Thus, (A) is a mutant variety.
(B) Pusa Centenary, (C) Pusa Kesari:
These cultivars were developed through traditional hybridization and selection at the Indian Agricultural Research Institute (IARI) in New Delhi.
Thus, (B) and (C) are not mutant varieties.
(D) Kundan:
This is another popular large-flowered chrysanthemum cultivar developed through induced mutation (using gamma irradiation on the parent variety) at NBRI, Lucknow.
Thus, (D) is a mutant variety.
Step 3: Final Answer:
The cultivars developed through induced mutation are Birbal Sahni (A) and Kundan (D).
This corresponds to Option (D).