How does sugriva defeat bali a. he uproots a giant tree trunk and hits bali with it. b. he stabs bali with a knife he hid in his pocket. c. he signals to rama to shoot him with a arrow. d. he becomes immortal and beats bali with his fist.

When near the Pampa lake both Rama and Laxman were in the search of Sita who was lost, this situation flowered the friendship between Rama and Sugriva.

In the Rishyamuka hill, Sugriva was hiding from Vali. Upon seeing Rama and Laxman from a distant place, he finds out their identity by sending Hanuman to identify. Hence, Hanuman was able to effectively enquire about them and assess their situation. Later upon introducing himself, Hanuman agrees that he assumed a form and that he is a monkey in real in direction of his master Sugriva. Hanuman leads them to Sugriva and in the time of fire Rama and Sugriva pledge to remain friends and that Rama assures to eliminate Bali. Such instance leads to lasting friendship and love between both.

Rama makes Sugriva assured about his power and considered Bali's crime to unpardonable of taking his brother's wife. Rama asks Sugriva to invite Bali for duel wherein Bali at first defeat Sugriva very badly and Rama is unable to identify who is Bali and Sugriva as both looked similar. For Sugriva's recognition, Rama asks Sugriva to wear garland. Upon calling Bali gain for duel while Bali arrives Sugriva signals to Rama to shoot him with an arrow and thus defeats Bali and Sugriva becomes the ruler of the Kishkindha.

C. He signals to rama to shoot him with a arrow.

the central idea is basically saying that juveniles that have committed a crime will not have the same consequences as the   adults that have. they will have a softer punishment than what the adults have that is harsh in some ways.