B. Long queues for getting water

Water shortage is a situation where there is an insufficient supply of water to meet the needs of people and the environment. It can occur due to various reasons such as drought, overpopulation, pollution, and inadequate infrastructure. In such situations, people face difficulties in accessing clean and adequate water for their daily needs.

One of the signs of water shortage is taps running dry. When there is a lack of water supply, the taps in households, public places, and businesses may stop producing water. This is a clear indication that there is a shortage of water in the area.

Another sign of water shortage is long queues for getting water. When there is limited water supply, people are forced to wait in long lines to collect water from alternative sources such as community wells, water tankers, or public taps. This indicates that there is not enough water available for everyone's needs, leading to inconvenience and hardships for the people.

Marches and protests for the demand of water also highlight the presence of water shortage. When people are facing severe water scarcity and their basic needs are not being met, they may organize marches, protests, and demonstrations to draw attention to the issue and demand immediate action from the authorities.

However, a family getting three buckets of water per person per day does not necessarily indicate water shortage. This information implies that the family has access to a certain amount of water, which may be sufficient for their daily needs. It does not provide any evidence of a shortage or lack of water supply in the area.

In conclusion, options a, b, and c all indicate water shortage, while option d does not. The correct answer is option d - A family gets three buckets of water per person per day.