How can one prepare for an arts exam consisting of ancient art of such; Nok, Ife etc. ?

Answer humanism;

Phil trash #1 aka danny boy

The answer to your question is true

Symbolism creates a "hidden meaning" of some sort without obviously showing it kind of like the "ophelia among the flowers" a beautiful peace but it does not look like anything right? if you  discover  the hidden meaning being the chaos and conflicts within ones mind youll see the art as having more meaning than just flowers.