What are gender symbols on the bathroom doors at school or other illustrated symbols that stand for some concept called

They are Isotypes, a form of pictoral (picture) language

i am 100% sure the answer is popular!

i believe the answer is: a.  abstract forms were often used to represent human figures.

representing human figures in abstract forms is often used in the geometric period, not hellenistic  period.   during the hellenistic  period,   aesthetic value derived from creating arts which mimic the actual shape of a certain object or individuals.

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