英语翻译He had expected gratitude for his disclosure,but instead

英语翻译
He had expected gratitude for his disclosure,but instead he encountered ________ bordering on hostility.
　　(A) patience
　　(B) discretion
　　(C) openness
　　(D) ineptitude
　　(E) indifference
我想知道这个句子是什么意思,这一项又是怎么选出来的啊