A. Sharing sweets while reading.
Explanation: Active reading has specific actions that ensure comprehension of the material. Commonly, active readers recommend the SQ3R method. This method (Survey, Question, Read, Recite, Review), ensures that the text being read is comprehended by the readers/learners. Establishing background knowledge of the topic fits in survey and questioning processes of the method. Illustrations and asking questions during the reading and discussing the story at the end establish a strong understanding of the text by the learners.
Therefore, the first choice (A. sharing sweets while reading), distracts learners from concentrating on the reading activity thus reducing comprehension.