Answer:
B. to hold someone's full interest
Step-by-step explanation:
By process of elimination we can eliminate the rest of the answers.
A. There is no information telling us that the slide can soak up liquid.
C & D. Absorb means neither of these in any context.
The answer is B. We can infer this from the next sentence after "absorb" is used. "The thrill... takes up all their attention!"