The correct option is C IgA
Colostrum is produced in the initial secretions of the mammary gland following the birth of offspring. Colostrum is most commonly distinguished from whole milk because it contains high concentrations of immunoglobulins (Ig), otherwise known as antibodies. Antibodies are proteins which function to identify and destroy disease-causing pathogens in livestock. The primary immunoglobulin in cow colostrum and milk is IgG, whereas the primary immunoglobulin in human milk is IgA. Colostrum is also a vital source of growth factors and nutritional elements such as protein, fat, milk sugar, vitamins and minerals.