Correct option is (b) one
The best explanation: A latrine is a toilet or an even simpler facility that is used as a toilet within a sanitation system. For example, it can be a communal trench in the earth in a camp to be used as emergency sanitation, a hole in the ground (pit latrine), or more advanced designs, including pour-flush systems.
The term “latrine” is still commonly used in emergency sanitation situations, as well as in army camps. Nowadays, the word “toilet” is more commonly used than “latrine”, except for simple systems like “pit latrine” or “trench latrine”.
The use of latrines was a major advance in sanitation over more basic practices such as open defecation and helped control the spread of many waterborne diseases.