As many as 25 percent of the cowboys who participated in the texas cattle drives were:

As many as 25 percent of the cowboys who participated in the Texas cattle drives were AFRICAN AMERICANS.
Cattle drive was a main economic activity in  the Western part of America during the 19th century. The west were known for cattle breeding and they usually have to move these cattle from the home ranches to the rail-heads where they will be bought. The distance between these two points is always great and it may takes as much as two to three months before the distances are covered. The cowboy are the ones that drive the cattle to their selling points. Texas was particular successful in cow farming and as at that time about one fourth of the cows boys are of African American origin.

answer: - b cells

explanation: -

there are many types of white blood cells present in our body. one such class of white blood cells are the lymphocytes. the b cells belong to the lymphocyte class of wbcs. the b cells perform their action against the pathogen by producing specialised proteins called as antibodies. these antibodies are produced as and when the b cells encounter pathogens in response to the antigens present on the surface of the pathogen. these antibodies bind to the antigens present on the pathogen and then, target them for destruction by other cells of the immune system.

so, the b cells mediate their action by identifying the antigens present on the surface of the pathogens and then producing antibodies in return to mediate its effect.