Seems to be a reasonable point to me. If everyone is already pre-elected, why evanglize? Please explain why it is wrong. Thanks.
Because God in His wisdom and grace has chosen the preaching of the Gospel by men to be the instrumental means by which He accomplishes the salvation of His people. As Scripture says, "How beautiful are the feet of those who preach the good news!" We do not know who God's elect are, but we know what God has set forth as His means of bringing them to faith and so with joy we preach the Gospel to all men entrusting the bounty of the harvest to Him who gives the increase (1 Cor 3:7).
As I have often said, the primary focus of evangelism is to be faithful, not convincing. Just as the primary focus of our works is to be faithful, not to earn something.
The proper response of man to the understanding of the sovereignty of God is not mere resignation and disinterest but rather peace, joy, thankfulness and devotion. Could He bring the elect to faith without our participation? Most assuredly so! But He has ordained the preaching of men as the "foolishness" by which He will bring His people to faith and salvation.
And so we go and make disciples of all nations.