Correct Answer - Option 3 : 145 m

**Given**

According to the question, when A covers the distance of 200 metes

B covers only 200 - 20 = 180 meters

Again, in 100 meter race, B beats C by 5 meters.

Hence, if B runs 100 metres, C runs 100 - 5 = 95 metres

**Calculation**

∵ If B runs 100 m, C runs = 95 m

∴ If B runs 180 m, C runs = (95/100)× 180

C runs = 171 m

∴ A : B : C = 200 : 180 : 171

Hence, A will beat C by = 200 - 171

A will beat C = 29 m in 200 m race.

**i.e. 29 × 5 = 145 m in 1 km race.**