Task: Class Relation Understanding (ontology: Food_Agriculture/PlantOntology)

Which of the following classes is one valid superclass of 'androecium primordium'?

A. 2.02 main shoot and axillary shoots visible at two nodes stage
B. B enlarged microsporocyte stage
C. 4 root elongation stage
D. floral organ primordium

Answer: floral organ primordium