You can have it upside down, or not be able to tell the directions on it.
The answer is D.
extra wording :)
Answer:
The main factor was water every civilization needs a water source then only can it flourish so nile valley flourished cause of the river the silt from it to farm and yearly flooding
Explanation:
Tang Dynasty was able to strengthen China thru the efforts of its Tang Taizong and Empress Wu in which the former brought back China's government and the latter empowered women. The Song dynasty continued the good governance and elevated the military system thru systematized testing.