Answer:
b) Submucosa is the strongest and most important layer for intestinal anastomosis. It has fibroblasts that will ultimately release collagen and hold the anastomosis together. This layer should be fully incorporated in the anastomosis.
Inverted vs everted anastomosis of intestine debate has been long going on, but now many prefer inverted because mucosa is exposed to mucosa and eventually degrades, joining the two submucosa layers together to cause healing by primary intention.