It has been suggested that older men in many cultures tend to marry women younger than themselves because men are genetically predisposed to seek female features associated with youthful fertility. This suggestion BEST illustrates:

chert is a sedimentary rock composed of microcrystalline or cryptocrystalline silica. with this little bit of information, you can come to the conclusion that your answer is c.  

explanation:

you didn't give any options but heres what i can tell you: an inference is likely to change based on additional observations. the latter is something that you have seen or sensed using your sensory organs while the former is like a conclusion out from what you have observed.