The Cycads, a Mostly Tropical Phylum of Gymnosperms, Evolved About

The cycads, a mostly tropical phylum of gymnosperms, evolved about 300 million years ago and were dominant forms during the age of the dinosaurs. Though their sperm are flagellated, their ovules are pollinated by beetles. These beetles get nutrition from the pollen and shelter from the microsporophylls. Upon visiting megasporophylls, the beetles transfer pollen to the exposed ovules. In cycads, pollen cones and seed cones are borne on different plants. Cycads synthesise neurotoxins, especially in the seeds, that are effective against most animals, including humans.
-If the beetles survive by consuming cycad pollen, then whether the beetles should be considered mutualists with, or parasites of, the cycads depends upon the ________.

A) extent to which their overall activities affect cycad reproduction
B) extent to which the beetles are affected by the neurotoxins
C) extent to which the beetles damage the cycad flowers
D) distance the beetles must travel between cycad microsporophylls and cycad megasporophylls

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