Rahim plans to Drive from city $\text{A}$ to station $\text{C}$, at the speed of $70$ km per hour, to catch a train arriving there from $\text{B}$. He must reach $\text{C}$ at least $15$ minutes before the arrival of the train. The train leaves $\text{B}$, located $500$ km south of $\text{A}$, at $8:00$ am and travels at a speed of $50$ km per hour. It is known that $\text{C}$ is located between west and northwest of $\text{B}$, with $\text{BC}$ at $60^{\circ}$ to $\text{AB}.$ The latest time by which Rahim must leave $\text{A}$ and still catch the train is closet to
- $6:15$ am
- $6:30$ am
- $6:45$ am
- $7:00$ am
- $7:15$ am