Why did God plant the tree of knowledge of good and evil in the Garden of Eden?

Why did God plant the tree of knowledge of good and evil in the Garden of Eden? Could not He have just not planted it there and let Adam and Eve eat from any tree? Or why did God forbid Adam/Eve in the first place?

I think its just a simple answer. True obedience. Without a choice, man can never exercise true obedience. With a choice, if man chooses to obey God rather than to give in to temptation, that is true obedience.

Just as we know that a child is truly obedient to his father when he chooses to do his homework on time rather than continue watching tv.

Just as one makes the choice not to click on the link to a pornographic website for fear of committing adultery. Just as one makes the choice not to utter/post senseless idle words for fear of losing a Christian testimony. Just as one makes the choice not to gossip behind the backs of others for fear of spreading false lies.

True obedience comes not in man having no choices to make, true obedience comes in man knowing and being exposed to temptation, yet still chooses the God favoring choice.

Let's learn the example of Jesus.

When Adam and Eve gave into their lusts and temptation and ate the fruit, Jesus though having fasted for 40 days and nights, was hungry, hung on and obeyed the Word of God, "Man shall not live on bread alone."(Matt 4:4)

When Eve were doubting God's perfect goodness and sovereignty that He withheld something good from them, Jesus trusted absolutely upon His Father and did not put Him to the test. (Matt 4:7)

When Eve lusted to be wise, to know good and evil, and to be like God, Jesus refused all splendor, riches and worshiped the Father with a servant's heart. (Matt 4:10)

How can we strive to obey God better?
1. To hold on to the Word of God
2. To trust in God absolutely
3. To worship Him only with a servant's heart.