Explanation:

Let’s break it down option by option:

- Achanakmar: This is, in fact, a recognized Biosphere Reserve. It’s in Chhattisgarh and is pretty rich in wildlife and forests.

- Agasthyamalai: Down south, straddling Kerala and Tamil Nadu, this one is also on the official Biosphere Reserve list.

- Dachigam: Now, here’s the catch. Dachigam is a National Park in Jammu & Kashmir, famous for the Hangul deer, but it’s *not* a Biosphere Reserve.

- Nokrek: Located in Meghalaya, Nokrek is indeed a Biosphere Reserve with some rare flora and fauna.

So, the right answer should be:

Option 3: Dachigam

What this really means is: if you’re hunting for the option that isn’t a Biosphere Reserve, “Dachigam” is your pick.