The order of Bihar according to population density in India is –

The correct answer is: C. eight

Bihar is the eighth most populous state in India, with a population of 109,797,300 as of 2011. The population density of Bihar is 1,109 people per square kilometer, which is higher than the national average of 382 people per square kilometer.

The following are the top 10 most populous states in India, along with their population density:

1. Uttar Pradesh (200,396,216; 828 people per square kilometer)
2. Maharashtra (112,374,333; 452 people per square kilometer)
3. West Bengal (91,347,736; 1,028 people per square kilometer)
4. Tamil Nadu (72,138,958; 555 people per square kilometer)
5. Andhra Pradesh (84,665,533; 328 people per square kilometer)
6. Madhya Pradesh (72,626,133; 231 people per square kilometer)
7. Rajasthan (68,632,861; 132 people per square kilometer)
8. Bihar (109,797,300; 1,109 people per square kilometer)
9. Gujarat (60,439,234; 308 people per square kilometer)
10. Karnataka (61,130,904; 319 people per square kilometer)

The population density of a state is calculated by dividing the total population of the state by the area of the state. The population density of Bihar is higher than the national average because the state has a large population and a relatively small area.