Can someone give me a detailed answer on the significance of the cross?

Jesus Christ died on a wooden cross in the month Nisan in A.D. 33. He died because some Jewish leaders plotted to pressure Pontius Pilate, the governor of Judea, to put Him to death by crucifixion (Matthew 27:1, 11-20; Luke 23:13-24). The Roman soldiers had already beaten him and placed a crown of thorns on his head (John 19:1-5). After the sentence to crucify Christ was announced (Luke 23:20-25; John 19:12-16),  Jesus  was forced to carry the cross on which He was to die (John 19:17-18). He had to carry the very tool of His death. Later it became the symbol of His death.

Explanation:

your answer is c) experiments with water vapor showed that elements combine in specific proportions.

they would have to clean it very clean