Option 1 states that a temperature reaching 25°C or more in summer is a geographical requirement for cotton cultivation. This is a correct statement as cotton requires warm temperatures to grow and thrive.

Option 2 states that moderate to light rainfall is a geographical requirement for cotton cultivation. This is also correct as cotton requires a certain amount of water to grow, but excessive rainfall can damage the crop.

Option 3, which is the correct answer, states that medium loam soil with good drainage is not a geographical requirement for cotton cultivation. This means that cotton can be grown in different types of soil as long as it has good drainage. This is correct as cotton is known to be adaptable to a wide range of soil types.

Option 4 states that a growing period of at least 100 frost-free days is a geographical requirement for cotton cultivation. This is also a correct statement as cotton is frost-sensitive and requires a longer growing period without frost.

In conclusion, option 3 is the correct answer as medium loam soil with good drainage is not a geographical requirement for cotton cultivation.