Which two details best show how Klaus Shubert’s experience in the historical setting develops the text’s theme. from Inge’s Wall

The great war came to an end in 1945, and Germany was divided. People in the East, where life was restrictive, fled in great numbers to the freedom they found in the West. To stop this, the government of the East built a wall in 1961.

One morning, when Klaus Schubert was 11 years old, he passed cement trucks and workers unloading steel rods and barbed wire as he walked to school. He returned hours later to find his view of the buildings, greenery, and other things he had seen earlier swallowed up by the sour-smelling cement and the snarling barbed wire. And worse, the people he had known were gone—friends and family alike. The government had said the wall was for the protection of the people on Klaus's side. But what had there been to fear?
That unanswered question became both an oppressive shroud over Klaus's childhood and a sinister playmate, as he often let his mind wander, imagining horrors or enemies that must have been so great that only such a great, grey, stone wall could keep them out. Then, Klaus grew into manhood, and he began to view the wall through another lens. It became an oppressor that the people in the East dared not question or appear to challenge in any way.