The cladogram of the kingdom animalia shows the relationship of selected animals based on their shared anatomical features. the black numbered squares represent features that are critical for forming each branch in the animal kingdom. square one represents a dorsal nerve cord, which means the animals in all the branches have a dorsal nerve cord. which numbered square would represent the trait "mammary glands? " a) 3 b) 4 c) 5 d) 6

6

Explanation:

white blood cells or wbc s are mainly 2 types-

1.agranulocytes

2.granulocytes

the monocytes or macrophages of agranulocytes , dendritic cells which are accessory leucocytes, and b cells which is one type of lymphocytes   identify the antigens present on the pathogen's surface. these three cells are called antigen presenting cells(apc) which are phagocytes and destroy the antigens by secreting antitoxins. besides this leukocyte is always plays vital role in the immunity of the body.