According to the Investigating Life essay, evidence of the vertebrate transition to land helped scientists discover the fossil , which has features of both fish and amphibians.

clinically, some people often have repeated allergies, eczema and respiratory infections or other parts of the infection, in this case, in addition to some routine tests such as tests for white blood cells, immunoglobulin series, lymphocyte subsets, etc., the five immune immunoglobulin tests are also necessary.

i believe your answer would be c.. : )