图中是一道物理题，请给出正确答案---**Question Stem:** 8. 如图所示，将一圆柱体从水中匀速提起直至下表面刚好离开水面，此过程容器底受到水的压强 P 随时间 t 变化图象大致如下列图中的．（ ） Translation: As shown in the figure, a cylinder is uniformly lifted from the water until its lower surface just leaves the water surface. During this process, the graph of the pressure P exerted by the water on the bottom of the container as a function of time t is approximately one of the following figures. ( ) **Initial Diagram Description:** * Type: Schematic diagram of an object in a container of liquid. * Elements: * A container with sloping sides, wider at the top than the bottom. * Liquid (presumably water, based on the text) inside the container. The liquid level is shown. * A rectangular object (labeled as a cylinder in the text) partially submerged in the liquid. * An upward arrow labeled 'v' indicating the velocity direction of the cylinder. * The lower part of the cylinder is submerged, the upper part is above the water level. **Options and Graph Descriptions:** * **Option A:** * Label: A. * Graph Type: Pressure (P) versus Time (t) graph. * Axes: Vertical axis represents pressure P, increasing upwards. Horizontal axis represents time t, increasing to the right. The origin O is at the bottom left. * Curve: Starts from a high value of P at t=0 and decreases over time, forming a convex downward curve. The curve ends at a certain time t where P is still greater than 0. * **Option B:** * Label: B. * Graph Type: Pressure (P) versus Time (t) graph. * Axes: Vertical axis represents pressure P, increasing upwards. Horizontal axis represents time t, increasing to the right. The origin O is at the bottom left. * Curve: Starts from a high constant value of P for a period of time, then decreases over time, forming a convex upward curve. The curve ends at a certain time t where P is still greater than 0. * **Option C:** * Label: C. * Graph Type: Pressure (P) versus Time (t) graph. * Axes: Vertical axis represents pressure P, increasing upwards. Horizontal axis represents time t, increasing to the right. The origin O is at the bottom left. * Curve: Starts from a high constant value of P for a period of time, then decreases linearly over time. The line ends at a certain time t where P is still greater than 0. * **Option D:** * Label: D. * Graph Type: Pressure (P) versus Time (t) graph. * Axes: Vertical axis represents pressure P, increasing upwards. Horizontal axis represents time t, increasing to the right. The origin O is at the bottom left. * Curve: Starts from a high constant value of P for a period of time, then decreases over time, forming a concave downward curve. The curve ends at a certain time t where P is still greater than 0. **Other Relevant Text:** * "公众号: Physics玩转物理123" (WeChat Official Account: Physics Fun with Physics 123) - This is a watermark or source indicator. It is not part of the question content itself but is present in the image.