- Chaman is older than only one friend, which means Chaman is the second youngest.
- Tapan is older than Karan, placing Karan in a younger position compared to Tapan.
- Only two people are older than Karan, so Tapan must be among those older than Karan.
- Baman is older than Tapan, placing Baman among the oldest.
- The order from youngest to oldest is: **Karan**, Chaman, Tapan, Baman (and thus Aman is oldest by deduction).

The youngest friend is Karan (Option 4).

- ✅ **Option 4: Karan is the youngest.**

YOUR ANSWER SEEMS WRONG.