A. Order
B. Class
C. Kingdom
D. Genus

A. Families
B. Order
C. Phyla
D. Kingdom

A. Class
B. Families
C. Phyla
D. Kingdom

A. Class
B. Genera
C. Order
D. Phyla

A. Species
B. Family
C. Order
D. Class

A. Family
B. Genus
C. Order
D. Class

A. Species
B. Genus
C. Family
D. Order

A. Family
B. Genus
C. Class
D. Species

A. Classification
B. Inheritance
C. Evolution
D. Behaviour

A. Cytology
B. Homology
C. Genetics
D. Biochemistry