Option 1, Brown Swiss, is a breed of cattle known for its excellent milk production. While it does produce a significant amount of milk, it is not the highest among the options provided.

Option 2, Holstein, is the correct answer. Holstein cattle are known for their exceptional milk production. They are the most common breed used in commercial dairy operations around the world. Holsteins are large and sturdy animals with a high milk yield, making them highly desirable for milk production.

Option 3, Dutch belted, is a breed of cattle that originated in the Netherlands. While they do produce milk, their milk yield is not as high as that of Holsteins.

Option 4, Blaarkop, is a native Dutch breed of cattle. It is primarily raised for meat production and is not known for its high milk yield.

In conclusion, Holstein cattle produce the highest amount of milk among the given options.