Supporting Question Answering (QA) tasks is the next step for lifelog retrieval systems, similar to the progression of the parent field of information retrieval. In this paper, we propose a new pipeline to tackle the QA task in the context of lifelogging, which is based on the open-domain QA pipeline. We incorporate this pipeline into a multimodal lifelog retrieval system, which allows users to submit questions prevalent to a lifelog and then suggests possible text answers based on multimodal data. A test collection is developed to facilitate the user study, the aim of which is to evaluate the effectiveness of the proposed system compared to a conventional lifelog retrieval system. The results show that the proposed system is more effective than the conventional system, in terms of both effectiveness and user satisfaction. The results also suggest that the proposed system is more valuable for novice users, while both systems are equally effective for experienced users.