In this task, you're given the title and three arbitrary sentences out of a five-sentence story. You are also given three additional sentence options, a, b, and c, that may or may not belong to the story. Your job is to pick the two options that seamlessly connect with the rest of the story; note that the selected choices may fit into the story at any point. Indicate your selected choices in order, i.e., as 'ab'/'bc'/'ac' and not as 'ba'/'ca'/'cb'. If options are equally plausible, pick the ones that make more sense.

Title: Julian had been suffering from back pains all week. It was beginning to interfere with his work. Luckily, within days his pain started to go away. Choices: a. He decided to replace his mattress that very day. b. As he tried to find the cause, he noticed his bed was very uniform. c. Apparently Tim had put his phone in the freezer.
ab