Which ability is not classified as a lapsing ability?

The ability that is not classified as a lapsing ability is one that grants +1/+1 until end of turn. Lapsing abilities are those that require a specific condition to continue to be in effect and typically end either after a certain condition is not met or at a specific time, usually marked by the phrase "until end of turn" or similar timeframes.

In contrast, the ability that provides a temporary boost such as +1/+1 until the end of the turn operates within a defined time frame and does not persist once that time frame has passed. Lapsing abilities, on the other hand, persist until the specific condition that triggers them is altered or removed, which does not apply to an effect that only lasts for a single turn.

The other abilities listed are classified as lapsing because they require ongoing conditions or states to remain active. For example, gaining control of a creature as long as a card remains indicates a dependence on that card's presence for the effect to continue. Similarly, providing an additional upkeep step implies a lasting change to the game structure which would need to be maintained, and exiling a permanent upon death represents a continuous interaction that would cease only when the related condition is no longer met.