Given a scientific question, generate a correct answer to it.

[EX Q]: What are the three types of symbiosis?
[EX A]: mutualism, parasitism, commensalism

[EX Q]: What is the process of the transfer of pollen from an anther to a stigma in angiosperms called?
[EX A]: pollination

[EX Q]: Hardness, density, color, and melting and boiling points are all considered what types of properties?
[EX A]:
physical