Suppose on an original map of scale 1 ratio 200,000is enlarge twice ​

The ratio will be 1:400,000.

Explanation:

An original map of scale 1 ratio 200,000 is enlarge twice ​then the ratio will be 1 : 400,000. Due to twice the ratio we can see the map more clearly as compared to the previous one. Due to twice enlargement of the map, we collect more information about the places we study and we can see many very object on the map which can't be seen earlier when the ratio is 1: 200,000 so we can say that twice enlargement makes the map more visible.

all three options are correct