A, B, C, D, E, and F are the six police stations in an area, which are connected by streets as shown below. Four teams - Team 1, Team 2, Team 3 and Team 4 patrol these streets continuously between 09:00 hrs. and 12:00 hrs. each day.

The teams need 30 minutes to cross a street connecting one police station to another. All four teams start from Station A at 09:00 hrs. and must return to Station A by 12:00 hrs. They can also pass via Station A at any point on their journeys.

The following facts are known.

1. None of the streets has more than one team traveling along it in any direction at any point in time.
2. Teams 2 and 3 are the only ones in stations E and D respectively at 10:00 hrs.
3. Teams 1 and 3 are the only ones in station E at 10:30 hrs.
4. Teams 1 and 4 are the only ones in stations B and E respectively at 11:30 hrs.
5. Team 1 and Team 4 are the only teams that patrol the street connecting stations A and E.
6. Team 4 never passes through Stations B, D or F.

Which team patrols the street connecting Stations D and E at 10:15 hrs?

To determine which team patrols the street connecting Stations D and E at 10:15 hrs, let us analyze the constraints and reconstruct the paths taken by the teams step-by-step.

First, we establish the timeline and the travel rules:
- The patrolling starts at 09:00 hrs and ends at 12:00 hrs.
- The time taken to traverse any street connecting two police stations is 30 minutes. Therefore, the teams arrive at police stations at 30-minute intervals: 09:00, 09:30, 10:00, 10:30, 11:00, 11:30, and 12:00.
- At 10:15 hrs (which is exactly halfway between 10:00 hrs and 10:30 hrs), any team patrolling a street must be in transit between the station it was at at 10:00 hrs and the station it reaches at 10:30 hrs.

Let us look at the facts related to the positions of the teams at 10:00 hrs and 10:30 hrs:
1. Fact 2: Teams 2 and 3 are the only ones in stations E and D respectively at 10:00 hrs.
This means at 10:00 hrs:
- Team 2 is at Station E.
- Team 3 is at Station D.
2. Fact 3: Teams 1 and 3 are the only ones in station E at 10:30 hrs.
This means at 10:30 hrs:
- Team 3 is at Station E.

Since Team 3 is at Station D at 10:00 hrs and is at Station E at 10:30 hrs, it must travel directly from Station D to Station E during this 30-minute interval.

Therefore, at the midpoint of this journey, which is 10:15 hrs, Team 3 is patrolling the street connecting Stations D and E.

Thus, the correct answer is Team 3.