The error presented in this sentence is that the antecedent of the pronoun “it” is not clear stated. To my mind, the pronoun "it" can refer to “spare time" or “reading”.
Can you please describe what is going on in the story?
Answer:
By the way he reacted and responded towards Her or other people or simply look at his facial expression
The best revision of the sentence is C.) Anna tried to hold back the dog, but she was just not strong enough for the bulk, power, and movement of the dog.