The preservation of the twelve stones by Joshua in Gilgal was to

The question is asking about the significance of the preservation of twelve stones by Joshua in Gilgal. The options are A) constituting a museum, B) founding a place of worship, C) reminding Israel of the crossing of River Jordan (which is the correct answer), and D) indicating that the site was a quarry.

When the Israelites crossed the River Jordan, God instructed Joshua to have twelve stones taken from the river and placed in Gilgal as a memorial to the miraculous crossing of the river. The stones were to serve as a reminder to future generations of the great miracle that God had performed on their behalf.

The preservation of these stones was not meant to create a museum or a place of worship, nor was it meant to indicate that the site was a quarry. The sole purpose was to remind Israel of God's faithfulness and power.

Therefore, the correct answer is C) remind Israel of the crossing of River Jordan. It is important for Christians to remember the great things that God has done for them in the past as a way to increase their faith and trust in Him for the future.