When the narrator says "It was a hard struggle for so small a child" （Line 4, Para. 5), sh

When the narrator says "It was a hard struggle for so small a child" (Line 4, Para. 5), she means that

A．saving her sick sister was too big a task for her as a child.

B．a child could sometimes do things beyond her imagination.

C．a child could not distinguish the reality and her fantasy.

D．her little sister"s condition had become too bad to do anything about.

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