Before humans began to devise ways to produce their own food, ...

[jessicacav]

Before humans began to devise ways to produce their own food, most of their time was devoted to which purpose?
 
  a. Raising livestock and crops c. Finding enough food to eat
  b. Developing select crop varieties d. Caring for the young

Question 2

____________________ or hybrid vigor comes from the cross breeding of two or more breeds to get an optimal animal.
 
  Fill in the blank(s) with correct word

[huda]

Answer to Question 1

C

Answer to Question 2

Heterosis