A few pages before this excerpt, Momaday mentions deep silence when nothing moves and it doesn't have any sound. Then, again he mentions this silence which is given in this excerpt. The meaning is not an allusion, it has got a direct meaning. The correct answer is the last option.
Franz Kafka who wrote the book ‘The Metamorphosis’ tells the story about a boy name Gregor Samsa who one days completely transforms from a human being to a giant insect.
Before his transformation, his family used to treat him well and used to Care for him.
But as soon as they came to know about Gregor’s transformation, their feelings towards him changed.
They started treating him in a very cruel way, rather Gregor himself started hating his own self for what he has become.