Answer:
Option B
Explanation:
There are several factors which causes famine across the globe such as
a) war between the countries
b) Crop failure due to unpredictable weather and pest attack
c) Fast pace of population growth and
d) Default government policies
Out of all the given options, option B is the most suitable cause of famine across the world. For instance case of Yemen can be considered where due to war scenarios extreme food scarcity emergency has been declared.