GRE General Test: RC-615404 GRE Reading Comprehension

Experiments show that insects can function as pollinators of cycads, rare, palm-like tropical plants. Furthermore, cycads removed from their native habitats-and therefore from insects native to those habitats—are usually infertile. Nevertheless, anecdotal reports of wind pollination in cycads cannot be ignored. The structure of cycads male cones is quite consistent with the wind dispersal of pollen, clouds of which are released from some of the larger cones. the male cone of Cycas circinalis, for example, sheds almost 100 cubic centimeters of pollen, most of which is probably. Dispersed by wind. Still, many male cycad cones are comparatively small and thus produce far less pollen. further- more, the structure of most female cycad cones seems inconsistent with direct pollination by wind. Only in the Cycas genus are the females’ ovules accessible to airborne pollen, since only in this genus are the ovules surrounded by a loose aggregation of megasporophylls rather than by a tight cone.
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According to the passage, the size of a male cycad cone directly influences which of the following?