Which of the following describes the fourth sublayer of layer 7 for continuous effects?

The fourth sublayer of layer 7 is specifically designated for handling power and toughness changes that come from counters. This means that any modifications to a creature's power or toughness that occur through counters are processed at this point in the game.

In Magic: The Gathering, counters such as +1/+1 counters or -1/-1 counters are applied in this sublayer. When a creature gains or loses counters, these changes are calculated along with the effects that modify power and toughness, but specifically those that stem from counters are dealt with in this fourth sublayer.

Understanding this hierarchy and organization of effects is vital for players and judges, as it determines how various effects interact and resolve. Other options address different aspects of power and toughness modifications, but they do not specifically describe effects stemming from counters, which is the focus of this particular sublayer.