When a resistance is bent in a circle, the resistors are are connected in parallel.
Each of the resistors (the 2 parallel resistors of the circle) have a resistance of 2 ohms.
So we get the following-
Req = R1 x R2 / R1R2 (where Req is equivalent resistance in parallel connections)
OR
1/Rp =1/R1 + 1/R2 ( where Rp is resistance in parallel )
1/Rp = 1/2 + 1/2
1/Rp = 2/2
1/Rp = 1
Rp = 1 ohm.