Choose C.
Hui Chong's Spring Flowers is a poem written by Su Shi in the Northern Song Dynasty.
There is also a title in the title, and a single title should be used in it.
Correction: Flowers in the Spring River is a poem written by Su Shi in the Northern Song Dynasty.
B, "You go and get it back now!" Mother said firmly, "How can you give away such a precious thing?"
There is something to say before and after, and you can't use colons after it, but commas.
Correction: "You go and get it back now!" Mother said firmly, "How can you give away such a precious thing?"
C. When I arrived in Jiangnan, I understood the benefits of these two sentences: "Miscellaneous peanut trees, swarms of warblers flying around".
correct
D, he told me: Only Cooper knows how this once barren mountain became today's prosperous world.
The whole sentence is not a question, so you can't use a question mark. In addition, a colon is not needed.
He told me that only Cooper knew how this once barren mountain became today's bustling world.