"Silk Road trade routes" is the one route among the following choices given in the question that he would most likely follow to achieve his goal. The correct option among all the options that are given in the question is the third option or option "c". I hope that this is the answer that has come to your desired help.
The first one. The use of irrigation.
It's being estimated that dinosaurs lived on Earth from about 237 million years ago to about 66 million years ago. So answers B and D are definately too "old", while answer A is too "young". I'd pick answer C as it's most probable.
