Here, the object of play is the written form of the answer, or, more precisely, the letters of which that form consists.
( Here ( , ( ( ( the object ) ( of play ) ) ( ( ( is ( ( ( ( ( ( the ( written form ) ) ( of ( the answer ) ) ) , ) or ) ( , ( ( more precisely ) , ) ) ) ( the letters ) ) ) ( ( of which ) ( ( that form ) consists ) ) ) . ) ) ) )
(ROOT (S (ADVP (RB Here)) (, ,) (NP (NP (DT the) (NN object)) (PP (IN of) (NP (NN play)))) (VP (VBZ is) (NP (NP (NP (DT the) (VBN written) (NN form)) (PP (IN of) (NP (DT the) (NN answer)))) (, ,) (CC or) (PRN (, ,) (ADVP (RBR more)) (ADVP (RB precisely)) (, ,)) (NP (DT the) (NNS letters))) (SBAR (WHPP (IN of) (WHNP (WDT which))) (S (NP (DT that) (NN form)) (VP (VBZ consists))))) (. .)))
That form contains letters and requires much study to understand. 
( ( That form ) ( ( ( ( contains letters ) and ) ( ( requires ( much study ) ) ( to understand ) ) ) . ) )
(ROOT (S (NP (DT That) (NN form)) (VP (VP (VBZ contains) (NP (NNS letters))) (CC and) (VP (VBZ requires) (NP (JJ much) (NN study)) (S (VP (TO to) (VP (VB understand)))))) (. .)))